feat(client): GrpcWebClientChannel on web targets via conditional import

Splits channel construction into two files selected at
compile-time via `if (dart.library.html)`:

  channel_factory_io.dart   — native ClientChannel (HTTP/2)
  channel_factory_web.dart  — GrpcWebClientChannel.xhr (HTTP/1.1)

HubClient._channel is now `ClientChannelBase` so both
implementations satisfy the same field type. dart:html-only
imports (`package:grpc/grpc_web.dart`) stay isolated from the
native compile path.

Pairs with the hub-side `fai_grpc_web` adapter crate
(fai/platform 0d07892) — `tonic-web` on the same port as
native gRPC, so one `fai serve` listener handles both
surfaces.

Signed-off-by: flemming-it <stefan.a.flemming@googlemail.com>

lib/src/channel_factory_io.dart

@@ -0,0 +1,21 @@
+// Native channel factory — plain gRPC over HTTP/2.
+// Selected on every non-web target (macOS, Linux, Windows, iOS,
+// Android) via the conditional import in hub_client.dart.
+
+import 'package:grpc/grpc.dart';
+import 'package:grpc/grpc_connection_interface.dart';
+
+import 'hub_client.dart' show HubEndpoint;
+
+ClientChannelBase createChannel(HubEndpoint endpoint) {
+  return ClientChannel(
+    endpoint.host,
+    port: endpoint.port,
+    options: ChannelOptions(
+      credentials: endpoint.secure
+          ? const ChannelCredentials.secure()
+          : const ChannelCredentials.insecure(),
+      idleTimeout: const Duration(minutes: 5),
+    ),
+  );
+}

lib/src/channel_factory_web.dart

@@ -0,0 +1,17 @@
+// Web channel factory — gRPC-Web over HTTP/1.1.
+// Selected on dart:html targets (Flutter web, Dart-for-web) via
+// the conditional import in hub_client.dart. The hub must be
+// running with `tonic-web` enabled — see fai_platform docs
+// architecture/protocol-surfaces.md.
+
+import 'package:grpc/grpc_connection_interface.dart';
+import 'package:grpc/grpc_web.dart';
+
+import 'hub_client.dart' show HubEndpoint;
+
+ClientChannelBase createChannel(HubEndpoint endpoint) {
+  final scheme = endpoint.secure ? 'https' : 'http';
+  return GrpcWebClientChannel.xhr(
+    Uri.parse('$scheme://${endpoint.host}:${endpoint.port}'),
+  );
+}

lib/src/generated/fai/v1/hub.pb.dart

@@ -336,6 +336,7 @@ class CapabilityEntry extends $pb.GeneratedMessage {
     $core.String? version,
     $core.String? moduleName,
     $core.String? moduleVersion,
+    $core.String? kind,
   }) {
     final $result = create();
     if (capability != null) {
@@ -350,6 +351,9 @@ class CapabilityEntry extends $pb.GeneratedMessage {
     if (moduleVersion != null) {
       $result.moduleVersion = moduleVersion;
     }
+    if (kind != null) {
+      $result.kind = kind;
+    }
     return $result;
   }
   CapabilityEntry._() : super();
@@ -361,6 +365,7 @@ class CapabilityEntry extends $pb.GeneratedMessage {
     ..aOS(2, _omitFieldNames ? '' : 'version')
     ..aOS(3, _omitFieldNames ? '' : 'moduleName')
     ..aOS(4, _omitFieldNames ? '' : 'moduleVersion')
+    ..aOS(5, _omitFieldNames ? '' : 'kind')
     ..hasRequiredFields = false
   ;
 
@@ -418,6 +423,24 @@ class CapabilityEntry extends $pb.GeneratedMessage {
   $core.bool hasModuleVersion() => $_has(3);
   @$pb.TagNumber(4)
   void clearModuleVersion() => $_clearField(4);
+
+  /// Where this capability comes from. Studio gates install
+  /// affordances on this — only "wasm" caps have a bundle to
+  /// install. Empty string is treated as "wasm" for
+  /// backwards-compat with older hubs.
+  ///   "wasm"      — declared by an installed WASM module
+  ///   "builtin"   — implemented in the hub itself
+  ///                 (e.g. system.approval)
+  ///   "federated" — discovered from an external MCP/n8n server;
+  ///                 not installable via the module-store path
+  @$pb.TagNumber(5)
+  $core.String get kind => $_getSZ(4);
+  @$pb.TagNumber(5)
+  set kind($core.String v) { $_setString(4, v); }
+  @$pb.TagNumber(5)
+  $core.bool hasKind() => $_has(4);
+  @$pb.TagNumber(5)
+  void clearKind() => $_clearField(5);
 }
 
 class ModuleInfoRequest extends $pb.GeneratedMessage {
@@ -471,6 +494,7 @@ class ModuleInfoResponse extends $pb.GeneratedMessage {
     $core.Iterable<$4.CapabilityRef>? provides,
     $core.Iterable<$core.String>? permissions,
     $core.String? directory,
+    $core.Iterable<$core.String>? acceptsMime,
   }) {
     final $result = create();
     if (name != null) {
@@ -488,6 +512,9 @@ class ModuleInfoResponse extends $pb.GeneratedMessage {
     if (directory != null) {
       $result.directory = directory;
     }
+    if (acceptsMime != null) {
+      $result.acceptsMime.addAll(acceptsMime);
+    }
     return $result;
   }
   ModuleInfoResponse._() : super();
@@ -500,6 +527,7 @@ class ModuleInfoResponse extends $pb.GeneratedMessage {
     ..pc<$4.CapabilityRef>(3, _omitFieldNames ? '' : 'provides', $pb.PbFieldType.PM, subBuilder: $4.CapabilityRef.create)
     ..pPS(4, _omitFieldNames ? '' : 'permissions')
     ..aOS(5, _omitFieldNames ? '' : 'directory')
+    ..pPS(6, _omitFieldNames ? '' : 'acceptsMime')
     ..hasRequiredFields = false
   ;
 
@@ -552,6 +580,14 @@ class ModuleInfoResponse extends $pb.GeneratedMessage {
   $core.bool hasDirectory() => $_has(4);
   @$pb.TagNumber(5)
   void clearDirectory() => $_clearField(5);
+
+  /// MIME allow-list for bytes-shaped inputs, copied verbatim
+  /// from `module.yaml`'s `accepts_mime:` field. Empty means
+  /// "no declared restriction". Studio uses this to pre-filter
+  /// the OS file-picker so operators don't pick a file the
+  /// module would reject.
+  @$pb.TagNumber(6)
+  $pb.PbList<$core.String> get acceptsMime => $_getList(5);
 }
 
 class CheckPermissionRequest extends $pb.GeneratedMessage {
@@ -2055,6 +2091,416 @@ class FetchModuleDocsResponse extends $pb.GeneratedMessage {
   void clearSourceUrl() => $_clearField(3);
 }
 
+class GetInstalledModuleDocsRequest extends $pb.GeneratedMessage {
+  factory GetInstalledModuleDocsRequest({
+    $core.String? name,
+    $core.String? locale,
+  }) {
+    final $result = create();
+    if (name != null) {
+      $result.name = name;
+    }
+    if (locale != null) {
+      $result.locale = locale;
+    }
+    return $result;
+  }
+  GetInstalledModuleDocsRequest._() : super();
+  factory GetInstalledModuleDocsRequest.fromBuffer($core.List<$core.int> i, [$pb.ExtensionRegistry r = $pb.ExtensionRegistry.EMPTY]) => create()..mergeFromBuffer(i, r);
+  factory GetInstalledModuleDocsRequest.fromJson($core.String i, [$pb.ExtensionRegistry r = $pb.ExtensionRegistry.EMPTY]) => create()..mergeFromJson(i, r);
+
+  static final $pb.BuilderInfo _i = $pb.BuilderInfo(_omitMessageNames ? '' : 'GetInstalledModuleDocsRequest', package: const $pb.PackageName(_omitMessageNames ? '' : 'fai.v1'), createEmptyInstance: create)
+    ..aOS(1, _omitFieldNames ? '' : 'name')
+    ..aOS(2, _omitFieldNames ? '' : 'locale')
+    ..hasRequiredFields = false
+  ;
+
+  @$core.Deprecated('See https://github.com/google/protobuf.dart/issues/998.')
+  GetInstalledModuleDocsRequest clone() => GetInstalledModuleDocsRequest()..mergeFromMessage(this);
+  @$core.Deprecated('See https://github.com/google/protobuf.dart/issues/998.')
+  GetInstalledModuleDocsRequest copyWith(void Function(GetInstalledModuleDocsRequest) updates) => super.copyWith((message) => updates(message as GetInstalledModuleDocsRequest)) as GetInstalledModuleDocsRequest;
+
+  $pb.BuilderInfo get info_ => _i;
+
+  @$core.pragma('dart2js:noInline')
+  static GetInstalledModuleDocsRequest create() => GetInstalledModuleDocsRequest._();
+  GetInstalledModuleDocsRequest createEmptyInstance() => create();
+  static $pb.PbList<GetInstalledModuleDocsRequest> createRepeated() => $pb.PbList<GetInstalledModuleDocsRequest>();
+  @$core.pragma('dart2js:noInline')
+  static GetInstalledModuleDocsRequest getDefault() => _defaultInstance ??= $pb.GeneratedMessage.$_defaultFor<GetInstalledModuleDocsRequest>(create);
+  static GetInstalledModuleDocsRequest? _defaultInstance;
+
+  /// Capability id (e.g. `text.extract`) or module-manifest name
+  /// (e.g. `text-extract`). The hub maps capability → module via
+  /// the registry; falls back to treating the name as a
+  /// directory name.
+  @$pb.TagNumber(1)
+  $core.String get name => $_getSZ(0);
+  @$pb.TagNumber(1)
+  set name($core.String v) { $_setString(0, v); }
+  @$pb.TagNumber(1)
+  $core.bool hasName() => $_has(0);
+  @$pb.TagNumber(1)
+  void clearName() => $_clearField(1);
+
+  /// Preferred locale code (e.g. "de", "en"). When set and not
+  /// "en", `MODULE.<locale>.md` is tried first; otherwise the
+  /// generic `MODULE.md` is used. Empty string = no preference.
+  @$pb.TagNumber(2)
+  $core.String get locale => $_getSZ(1);
+  @$pb.TagNumber(2)
+  set locale($core.String v) { $_setString(1, v); }
+  @$pb.TagNumber(2)
+  $core.bool hasLocale() => $_has(1);
+  @$pb.TagNumber(2)
+  void clearLocale() => $_clearField(2);
+}
+
+class GetInstalledModuleDocsResponse extends $pb.GeneratedMessage {
+  factory GetInstalledModuleDocsResponse({
+    $core.String? text,
+    $core.String? sourcePath,
+    $core.bool? notInstalled,
+  }) {
+    final $result = create();
+    if (text != null) {
+      $result.text = text;
+    }
+    if (sourcePath != null) {
+      $result.sourcePath = sourcePath;
+    }
+    if (notInstalled != null) {
+      $result.notInstalled = notInstalled;
+    }
+    return $result;
+  }
+  GetInstalledModuleDocsResponse._() : super();
+  factory GetInstalledModuleDocsResponse.fromBuffer($core.List<$core.int> i, [$pb.ExtensionRegistry r = $pb.ExtensionRegistry.EMPTY]) => create()..mergeFromBuffer(i, r);
+  factory GetInstalledModuleDocsResponse.fromJson($core.String i, [$pb.ExtensionRegistry r = $pb.ExtensionRegistry.EMPTY]) => create()..mergeFromJson(i, r);
+
+  static final $pb.BuilderInfo _i = $pb.BuilderInfo(_omitMessageNames ? '' : 'GetInstalledModuleDocsResponse', package: const $pb.PackageName(_omitMessageNames ? '' : 'fai.v1'), createEmptyInstance: create)
+    ..aOS(1, _omitFieldNames ? '' : 'text')
+    ..aOS(2, _omitFieldNames ? '' : 'sourcePath')
+    ..aOB(3, _omitFieldNames ? '' : 'notInstalled')
+    ..hasRequiredFields = false
+  ;
+
+  @$core.Deprecated('See https://github.com/google/protobuf.dart/issues/998.')
+  GetInstalledModuleDocsResponse clone() => GetInstalledModuleDocsResponse()..mergeFromMessage(this);
+  @$core.Deprecated('See https://github.com/google/protobuf.dart/issues/998.')
+  GetInstalledModuleDocsResponse copyWith(void Function(GetInstalledModuleDocsResponse) updates) => super.copyWith((message) => updates(message as GetInstalledModuleDocsResponse)) as GetInstalledModuleDocsResponse;
+
+  $pb.BuilderInfo get info_ => _i;
+
+  @$core.pragma('dart2js:noInline')
+  static GetInstalledModuleDocsResponse create() => GetInstalledModuleDocsResponse._();
+  GetInstalledModuleDocsResponse createEmptyInstance() => create();
+  static $pb.PbList<GetInstalledModuleDocsResponse> createRepeated() => $pb.PbList<GetInstalledModuleDocsResponse>();
+  @$core.pragma('dart2js:noInline')
+  static GetInstalledModuleDocsResponse getDefault() => _defaultInstance ??= $pb.GeneratedMessage.$_defaultFor<GetInstalledModuleDocsResponse>(create);
+  static GetInstalledModuleDocsResponse? _defaultInstance;
+
+  /// Markdown body. Empty when the module is installed but ships
+  /// no inline docs — Studio uses this to hide its docs button.
+  @$pb.TagNumber(1)
+  $core.String get text => $_getSZ(0);
+  @$pb.TagNumber(1)
+  set text($core.String v) { $_setString(0, v); }
+  @$pb.TagNumber(1)
+  $core.bool hasText() => $_has(0);
+  @$pb.TagNumber(1)
+  void clearText() => $_clearField(1);
+
+  /// Absolute path on the hub host that the body was read from,
+  /// for "loaded from /path/MODULE.md" hints in Studio. Empty
+  /// when text is empty.
+  @$pb.TagNumber(2)
+  $core.String get sourcePath => $_getSZ(1);
+  @$pb.TagNumber(2)
+  set sourcePath($core.String v) { $_setString(1, v); }
+  @$pb.TagNumber(2)
+  $core.bool hasSourcePath() => $_has(1);
+  @$pb.TagNumber(2)
+  void clearSourcePath() => $_clearField(2);
+
+  /// True when the module wasn't installed at all. Distinct from
+  /// "installed but no inline docs" so Studio can show different
+  /// affordances ("install first" vs "no inline docs available").
+  @$pb.TagNumber(3)
+  $core.bool get notInstalled => $_getBF(2);
+  @$pb.TagNumber(3)
+  set notInstalled($core.bool v) { $_setBool(2, v); }
+  @$pb.TagNumber(3)
+  $core.bool hasNotInstalled() => $_has(2);
+  @$pb.TagNumber(3)
+  void clearNotInstalled() => $_clearField(3);
+}
+
+class InvokePluginThemeRequest extends $pb.GeneratedMessage {
+  factory InvokePluginThemeRequest({
+    $core.String? capability,
+    $core.String? brightness,
+  }) {
+    final $result = create();
+    if (capability != null) {
+      $result.capability = capability;
+    }
+    if (brightness != null) {
+      $result.brightness = brightness;
+    }
+    return $result;
+  }
+  InvokePluginThemeRequest._() : super();
+  factory InvokePluginThemeRequest.fromBuffer($core.List<$core.int> i, [$pb.ExtensionRegistry r = $pb.ExtensionRegistry.EMPTY]) => create()..mergeFromBuffer(i, r);
+  factory InvokePluginThemeRequest.fromJson($core.String i, [$pb.ExtensionRegistry r = $pb.ExtensionRegistry.EMPTY]) => create()..mergeFromJson(i, r);
+
+  static final $pb.BuilderInfo _i = $pb.BuilderInfo(_omitMessageNames ? '' : 'InvokePluginThemeRequest', package: const $pb.PackageName(_omitMessageNames ? '' : 'fai.v1'), createEmptyInstance: create)
+    ..aOS(1, _omitFieldNames ? '' : 'capability')
+    ..aOS(2, _omitFieldNames ? '' : 'brightness')
+    ..hasRequiredFields = false
+  ;
+
+  @$core.Deprecated('See https://github.com/google/protobuf.dart/issues/998.')
+  InvokePluginThemeRequest clone() => InvokePluginThemeRequest()..mergeFromMessage(this);
+  @$core.Deprecated('See https://github.com/google/protobuf.dart/issues/998.')
+  InvokePluginThemeRequest copyWith(void Function(InvokePluginThemeRequest) updates) => super.copyWith((message) => updates(message as InvokePluginThemeRequest)) as InvokePluginThemeRequest;
+
+  $pb.BuilderInfo get info_ => _i;
+
+  @$core.pragma('dart2js:noInline')
+  static InvokePluginThemeRequest create() => InvokePluginThemeRequest._();
+  InvokePluginThemeRequest createEmptyInstance() => create();
+  static $pb.PbList<InvokePluginThemeRequest> createRepeated() => $pb.PbList<InvokePluginThemeRequest>();
+  @$core.pragma('dart2js:noInline')
+  static InvokePluginThemeRequest getDefault() => _defaultInstance ??= $pb.GeneratedMessage.$_defaultFor<InvokePluginThemeRequest>(create);
+  static InvokePluginThemeRequest? _defaultInstance;
+
+  /// Capability name the operator asked for, e.g.
+  /// `studio.theme.solarized`. The hub maps this to the
+  /// installed plugin directory.
+  @$pb.TagNumber(1)
+  $core.String get capability => $_getSZ(0);
+  @$pb.TagNumber(1)
+  set capability($core.String v) { $_setString(0, v); }
+  @$pb.TagNumber(1)
+  $core.bool hasCapability() => $_has(0);
+  @$pb.TagNumber(1)
+  void clearCapability() => $_clearField(1);
+
+  /// "light" or "dark" — the plugin returns a ColorScheme
+  /// for this brightness. Plugins that don't recognise the
+  /// value return PluginError::declined and the hub
+  /// surfaces that as a friendly error.
+  @$pb.TagNumber(2)
+  $core.String get brightness => $_getSZ(1);
+  @$pb.TagNumber(2)
+  set brightness($core.String v) { $_setString(1, v); }
+  @$pb.TagNumber(2)
+  $core.bool hasBrightness() => $_has(1);
+  @$pb.TagNumber(2)
+  void clearBrightness() => $_clearField(2);
+}
+
+class InvokePluginTranslateRequest extends $pb.GeneratedMessage {
+  factory InvokePluginTranslateRequest({
+    $core.String? capability,
+    $core.String? text,
+    $core.String? fromLocale,
+    $core.String? toLocale,
+  }) {
+    final $result = create();
+    if (capability != null) {
+      $result.capability = capability;
+    }
+    if (text != null) {
+      $result.text = text;
+    }
+    if (fromLocale != null) {
+      $result.fromLocale = fromLocale;
+    }
+    if (toLocale != null) {
+      $result.toLocale = toLocale;
+    }
+    return $result;
+  }
+  InvokePluginTranslateRequest._() : super();
+  factory InvokePluginTranslateRequest.fromBuffer($core.List<$core.int> i, [$pb.ExtensionRegistry r = $pb.ExtensionRegistry.EMPTY]) => create()..mergeFromBuffer(i, r);
+  factory InvokePluginTranslateRequest.fromJson($core.String i, [$pb.ExtensionRegistry r = $pb.ExtensionRegistry.EMPTY]) => create()..mergeFromJson(i, r);
+
+  static final $pb.BuilderInfo _i = $pb.BuilderInfo(_omitMessageNames ? '' : 'InvokePluginTranslateRequest', package: const $pb.PackageName(_omitMessageNames ? '' : 'fai.v1'), createEmptyInstance: create)
+    ..aOS(1, _omitFieldNames ? '' : 'capability')
+    ..aOS(2, _omitFieldNames ? '' : 'text')
+    ..aOS(3, _omitFieldNames ? '' : 'fromLocale')
+    ..aOS(4, _omitFieldNames ? '' : 'toLocale')
+    ..hasRequiredFields = false
+  ;
+
+  @$core.Deprecated('See https://github.com/google/protobuf.dart/issues/998.')
+  InvokePluginTranslateRequest clone() => InvokePluginTranslateRequest()..mergeFromMessage(this);
+  @$core.Deprecated('See https://github.com/google/protobuf.dart/issues/998.')
+  InvokePluginTranslateRequest copyWith(void Function(InvokePluginTranslateRequest) updates) => super.copyWith((message) => updates(message as InvokePluginTranslateRequest)) as InvokePluginTranslateRequest;
+
+  $pb.BuilderInfo get info_ => _i;
+
+  @$core.pragma('dart2js:noInline')
+  static InvokePluginTranslateRequest create() => InvokePluginTranslateRequest._();
+  InvokePluginTranslateRequest createEmptyInstance() => create();
+  static $pb.PbList<InvokePluginTranslateRequest> createRepeated() => $pb.PbList<InvokePluginTranslateRequest>();
+  @$core.pragma('dart2js:noInline')
+  static InvokePluginTranslateRequest getDefault() => _defaultInstance ??= $pb.GeneratedMessage.$_defaultFor<InvokePluginTranslateRequest>(create);
+  static InvokePluginTranslateRequest? _defaultInstance;
+
+  /// Capability name (e.g. `studio.translate.ollama`).
+  @$pb.TagNumber(1)
+  $core.String get capability => $_getSZ(0);
+  @$pb.TagNumber(1)
+  set capability($core.String v) { $_setString(0, v); }
+  @$pb.TagNumber(1)
+  $core.bool hasCapability() => $_has(0);
+  @$pb.TagNumber(1)
+  void clearCapability() => $_clearField(1);
+
+  /// Text to translate. UTF-8, arbitrary length the plugin
+  /// tolerates.
+  @$pb.TagNumber(2)
+  $core.String get text => $_getSZ(1);
+  @$pb.TagNumber(2)
+  set text($core.String v) { $_setString(1, v); }
+  @$pb.TagNumber(2)
+  $core.bool hasText() => $_has(1);
+  @$pb.TagNumber(2)
+  void clearText() => $_clearField(2);
+
+  /// BCP-47 source locale. Empty = let the plugin auto-detect.
+  @$pb.TagNumber(3)
+  $core.String get fromLocale => $_getSZ(2);
+  @$pb.TagNumber(3)
+  set fromLocale($core.String v) { $_setString(2, v); }
+  @$pb.TagNumber(3)
+  $core.bool hasFromLocale() => $_has(2);
+  @$pb.TagNumber(3)
+  void clearFromLocale() => $_clearField(3);
+
+  /// BCP-47 target locale. Required; the host always knows it.
+  @$pb.TagNumber(4)
+  $core.String get toLocale => $_getSZ(3);
+  @$pb.TagNumber(4)
+  set toLocale($core.String v) { $_setString(3, v); }
+  @$pb.TagNumber(4)
+  $core.bool hasToLocale() => $_has(3);
+  @$pb.TagNumber(4)
+  void clearToLocale() => $_clearField(4);
+}
+
+class InvokePluginTranslateResponse extends $pb.GeneratedMessage {
+  factory InvokePluginTranslateResponse({
+    $core.String? translated,
+  }) {
+    final $result = create();
+    if (translated != null) {
+      $result.translated = translated;
+    }
+    return $result;
+  }
+  InvokePluginTranslateResponse._() : super();
+  factory InvokePluginTranslateResponse.fromBuffer($core.List<$core.int> i, [$pb.ExtensionRegistry r = $pb.ExtensionRegistry.EMPTY]) => create()..mergeFromBuffer(i, r);
+  factory InvokePluginTranslateResponse.fromJson($core.String i, [$pb.ExtensionRegistry r = $pb.ExtensionRegistry.EMPTY]) => create()..mergeFromJson(i, r);
+
+  static final $pb.BuilderInfo _i = $pb.BuilderInfo(_omitMessageNames ? '' : 'InvokePluginTranslateResponse', package: const $pb.PackageName(_omitMessageNames ? '' : 'fai.v1'), createEmptyInstance: create)
+    ..aOS(1, _omitFieldNames ? '' : 'translated')
+    ..hasRequiredFields = false
+  ;
+
+  @$core.Deprecated('See https://github.com/google/protobuf.dart/issues/998.')
+  InvokePluginTranslateResponse clone() => InvokePluginTranslateResponse()..mergeFromMessage(this);
+  @$core.Deprecated('See https://github.com/google/protobuf.dart/issues/998.')
+  InvokePluginTranslateResponse copyWith(void Function(InvokePluginTranslateResponse) updates) => super.copyWith((message) => updates(message as InvokePluginTranslateResponse)) as InvokePluginTranslateResponse;
+
+  $pb.BuilderInfo get info_ => _i;
+
+  @$core.pragma('dart2js:noInline')
+  static InvokePluginTranslateResponse create() => InvokePluginTranslateResponse._();
+  InvokePluginTranslateResponse createEmptyInstance() => create();
+  static $pb.PbList<InvokePluginTranslateResponse> createRepeated() => $pb.PbList<InvokePluginTranslateResponse>();
+  @$core.pragma('dart2js:noInline')
+  static InvokePluginTranslateResponse getDefault() => _defaultInstance ??= $pb.GeneratedMessage.$_defaultFor<InvokePluginTranslateResponse>(create);
+  static InvokePluginTranslateResponse? _defaultInstance;
+
+  /// Translated text. Returns verbatim what the plugin
+  /// emits — no normalisation by the hub.
+  @$pb.TagNumber(1)
+  $core.String get translated => $_getSZ(0);
+  @$pb.TagNumber(1)
+  set translated($core.String v) { $_setString(0, v); }
+  @$pb.TagNumber(1)
+  $core.bool hasTranslated() => $_has(0);
+  @$pb.TagNumber(1)
+  void clearTranslated() => $_clearField(1);
+}
+
+class InvokePluginThemeResponse extends $pb.GeneratedMessage {
+  factory InvokePluginThemeResponse({
+    $core.String? brightness,
+    $core.Iterable<$core.int>? tokens,
+  }) {
+    final $result = create();
+    if (brightness != null) {
+      $result.brightness = brightness;
+    }
+    if (tokens != null) {
+      $result.tokens.addAll(tokens);
+    }
+    return $result;
+  }
+  InvokePluginThemeResponse._() : super();
+  factory InvokePluginThemeResponse.fromBuffer($core.List<$core.int> i, [$pb.ExtensionRegistry r = $pb.ExtensionRegistry.EMPTY]) => create()..mergeFromBuffer(i, r);
+  factory InvokePluginThemeResponse.fromJson($core.String i, [$pb.ExtensionRegistry r = $pb.ExtensionRegistry.EMPTY]) => create()..mergeFromJson(i, r);
+
+  static final $pb.BuilderInfo _i = $pb.BuilderInfo(_omitMessageNames ? '' : 'InvokePluginThemeResponse', package: const $pb.PackageName(_omitMessageNames ? '' : 'fai.v1'), createEmptyInstance: create)
+    ..aOS(1, _omitFieldNames ? '' : 'brightness')
+    ..p<$core.int>(2, _omitFieldNames ? '' : 'tokens', $pb.PbFieldType.KU3)
+    ..hasRequiredFields = false
+  ;
+
+  @$core.Deprecated('See https://github.com/google/protobuf.dart/issues/998.')
+  InvokePluginThemeResponse clone() => InvokePluginThemeResponse()..mergeFromMessage(this);
+  @$core.Deprecated('See https://github.com/google/protobuf.dart/issues/998.')
+  InvokePluginThemeResponse copyWith(void Function(InvokePluginThemeResponse) updates) => super.copyWith((message) => updates(message as InvokePluginThemeResponse)) as InvokePluginThemeResponse;
+
+  $pb.BuilderInfo get info_ => _i;
+
+  @$core.pragma('dart2js:noInline')
+  static InvokePluginThemeResponse create() => InvokePluginThemeResponse._();
+  InvokePluginThemeResponse createEmptyInstance() => create();
+  static $pb.PbList<InvokePluginThemeResponse> createRepeated() => $pb.PbList<InvokePluginThemeResponse>();
+  @$core.pragma('dart2js:noInline')
+  static InvokePluginThemeResponse getDefault() => _defaultInstance ??= $pb.GeneratedMessage.$_defaultFor<InvokePluginThemeResponse>(create);
+  static InvokePluginThemeResponse? _defaultInstance;
+
+  /// Echo of the brightness input. Plugins are expected to
+  /// round-trip it; if they don't the client treats that as
+  /// a contract violation.
+  @$pb.TagNumber(1)
+  $core.String get brightness => $_getSZ(0);
+  @$pb.TagNumber(1)
+  set brightness($core.String v) { $_setString(0, v); }
+  @$pb.TagNumber(1)
+  $core.bool hasBrightness() => $_has(0);
+  @$pb.TagNumber(1)
+  void clearBrightness() => $_clearField(1);
+
+  /// 14 ARGB tokens in Material 3 order:
+  ///   primary, on_primary, secondary, on_secondary,
+  ///   tertiary, on_tertiary, error, on_error,
+  ///   surface, on_surface, surface_variant,
+  ///   on_surface_variant, outline, outline_variant.
+  /// Studio merges any missing slot (well-behaved plugins
+  /// send all 14) with its built-in fallback before
+  /// applying the scheme.
+  @$pb.TagNumber(2)
+  $pb.PbList<$core.int> get tokens => $_getList(1);
+}
+
 class ListApprovalsRequest extends $pb.GeneratedMessage {
   factory ListApprovalsRequest({
     $core.Iterable<$core.String>? statuses,

lib/src/generated/fai/v1/hub.pbgrpc.dart

@@ -175,6 +175,18 @@ class HubAdminClient extends $grpc.Client {
       '/fai.v1.HubAdmin/FetchModuleDocs',
       ($0.FetchModuleDocsRequest value) => value.writeToBuffer(),
       ($core.List<$core.int> value) => $0.FetchModuleDocsResponse.fromBuffer(value));
+  static final _$getInstalledModuleDocs = $grpc.ClientMethod<$0.GetInstalledModuleDocsRequest, $0.GetInstalledModuleDocsResponse>(
+      '/fai.v1.HubAdmin/GetInstalledModuleDocs',
+      ($0.GetInstalledModuleDocsRequest value) => value.writeToBuffer(),
+      ($core.List<$core.int> value) => $0.GetInstalledModuleDocsResponse.fromBuffer(value));
+  static final _$invokePluginTheme = $grpc.ClientMethod<$0.InvokePluginThemeRequest, $0.InvokePluginThemeResponse>(
+      '/fai.v1.HubAdmin/InvokePluginTheme',
+      ($0.InvokePluginThemeRequest value) => value.writeToBuffer(),
+      ($core.List<$core.int> value) => $0.InvokePluginThemeResponse.fromBuffer(value));
+  static final _$invokePluginTranslate = $grpc.ClientMethod<$0.InvokePluginTranslateRequest, $0.InvokePluginTranslateResponse>(
+      '/fai.v1.HubAdmin/InvokePluginTranslate',
+      ($0.InvokePluginTranslateRequest value) => value.writeToBuffer(),
+      ($core.List<$core.int> value) => $0.InvokePluginTranslateResponse.fromBuffer(value));
   static final _$listApprovals = $grpc.ClientMethod<$0.ListApprovalsRequest, $0.ApprovalList>(
       '/fai.v1.HubAdmin/ListApprovals',
       ($0.ListApprovalsRequest value) => value.writeToBuffer(),
@@ -356,6 +368,37 @@ class HubAdminClient extends $grpc.Client {
     return $createUnaryCall(_$fetchModuleDocs, request, options: options);
   }
 
+  /// Read the inline-docs (MODULE.md / MODULE.<locale>.md) of an
+  /// installed module from disk. No network fetch, no provider-
+  /// specific URL probing — the docs ship in the .fai bundle and
+  /// live next to module.wasm on disk after install. Returns an
+  /// empty body when the module is installed but ships no inline
+  /// docs; Studio uses that to hide the docs button entirely.
+  $grpc.ResponseFuture<$0.GetInstalledModuleDocsResponse> getInstalledModuleDocs($0.GetInstalledModuleDocsRequest request, {$grpc.CallOptions? options}) {
+    return $createUnaryCall(_$getInstalledModuleDocs, request, options: options);
+  }
+
+  /// Invoke an installed Studio plugin's `theme` hook. Returns
+  /// the plugin's proposed Material 3 ColorScheme for the
+  /// brightness the caller asked for ("light" or "dark"). The
+  /// first end-to-end RPC of the Studio-plugin subsystem; the
+  /// `translate` and `output-view` hooks get their own RPCs as
+  /// the matching Studio surfaces ship.
+  $grpc.ResponseFuture<$0.InvokePluginThemeResponse> invokePluginTheme($0.InvokePluginThemeRequest request, {$grpc.CallOptions? options}) {
+    return $createUnaryCall(_$invokePluginTheme, request, options: options);
+  }
+
+  /// Invoke an installed Studio plugin's `translate` hook.
+  /// The first user surface that consumes this is Studio's
+  /// FaiEnBadge — when an operator has a translate plugin
+  /// installed, server-supplied English text (MCP tool
+  /// descriptions, n8n endpoint names) gets translated
+  /// on-the-fly into the active locale instead of carrying
+  /// the honest-but-rough [EN] badge.
+  $grpc.ResponseFuture<$0.InvokePluginTranslateResponse> invokePluginTranslate($0.InvokePluginTranslateRequest request, {$grpc.CallOptions? options}) {
+    return $createUnaryCall(_$invokePluginTranslate, request, options: options);
+  }
+
   /// List system.approval@^0 entries, optionally filtered by status.
   $grpc.ResponseFuture<$0.ApprovalList> listApprovals($0.ListApprovalsRequest request, {$grpc.CallOptions? options}) {
     return $createUnaryCall(_$listApprovals, request, options: options);
@@ -639,6 +682,27 @@ abstract class HubAdminServiceBase extends $grpc.Service {
         false,
         ($core.List<$core.int> value) => $0.FetchModuleDocsRequest.fromBuffer(value),
         ($0.FetchModuleDocsResponse value) => value.writeToBuffer()));
+    $addMethod($grpc.ServiceMethod<$0.GetInstalledModuleDocsRequest, $0.GetInstalledModuleDocsResponse>(
+        'GetInstalledModuleDocs',
+        getInstalledModuleDocs_Pre,
+        false,
+        false,
+        ($core.List<$core.int> value) => $0.GetInstalledModuleDocsRequest.fromBuffer(value),
+        ($0.GetInstalledModuleDocsResponse value) => value.writeToBuffer()));
+    $addMethod($grpc.ServiceMethod<$0.InvokePluginThemeRequest, $0.InvokePluginThemeResponse>(
+        'InvokePluginTheme',
+        invokePluginTheme_Pre,
+        false,
+        false,
+        ($core.List<$core.int> value) => $0.InvokePluginThemeRequest.fromBuffer(value),
+        ($0.InvokePluginThemeResponse value) => value.writeToBuffer()));
+    $addMethod($grpc.ServiceMethod<$0.InvokePluginTranslateRequest, $0.InvokePluginTranslateResponse>(
+        'InvokePluginTranslate',
+        invokePluginTranslate_Pre,
+        false,
+        false,
+        ($core.List<$core.int> value) => $0.InvokePluginTranslateRequest.fromBuffer(value),
+        ($0.InvokePluginTranslateResponse value) => value.writeToBuffer()));
     $addMethod($grpc.ServiceMethod<$0.ListApprovalsRequest, $0.ApprovalList>(
         'ListApprovals',
         listApprovals_Pre,
@@ -875,6 +939,18 @@ abstract class HubAdminServiceBase extends $grpc.Service {
     return fetchModuleDocs($call, await $request);
   }
 
+  $async.Future<$0.GetInstalledModuleDocsResponse> getInstalledModuleDocs_Pre($grpc.ServiceCall $call, $async.Future<$0.GetInstalledModuleDocsRequest> $request) async {
+    return getInstalledModuleDocs($call, await $request);
+  }
+
+  $async.Future<$0.InvokePluginThemeResponse> invokePluginTheme_Pre($grpc.ServiceCall $call, $async.Future<$0.InvokePluginThemeRequest> $request) async {
+    return invokePluginTheme($call, await $request);
+  }
+
+  $async.Future<$0.InvokePluginTranslateResponse> invokePluginTranslate_Pre($grpc.ServiceCall $call, $async.Future<$0.InvokePluginTranslateRequest> $request) async {
+    return invokePluginTranslate($call, await $request);
+  }
+
   $async.Future<$0.ApprovalList> listApprovals_Pre($grpc.ServiceCall $call, $async.Future<$0.ListApprovalsRequest> $request) async {
     return listApprovals($call, await $request);
   }
@@ -992,6 +1068,9 @@ abstract class HubAdminServiceBase extends $grpc.Service {
   $async.Future<$0.InstallModuleResponse> installModule($grpc.ServiceCall call, $0.InstallModuleRequest request);
   $async.Future<$0.UninstallModuleResponse> uninstallModule($grpc.ServiceCall call, $0.UninstallModuleRequest request);
   $async.Future<$0.FetchModuleDocsResponse> fetchModuleDocs($grpc.ServiceCall call, $0.FetchModuleDocsRequest request);
+  $async.Future<$0.GetInstalledModuleDocsResponse> getInstalledModuleDocs($grpc.ServiceCall call, $0.GetInstalledModuleDocsRequest request);
+  $async.Future<$0.InvokePluginThemeResponse> invokePluginTheme($grpc.ServiceCall call, $0.InvokePluginThemeRequest request);
+  $async.Future<$0.InvokePluginTranslateResponse> invokePluginTranslate($grpc.ServiceCall call, $0.InvokePluginTranslateRequest request);
   $async.Future<$0.ApprovalList> listApprovals($grpc.ServiceCall call, $0.ListApprovalsRequest request);
   $async.Future<$0.DecideApprovalResponse> decideApproval($grpc.ServiceCall call, $0.DecideApprovalRequest request);
   $async.Future<$0.VerifyEventChainResponse> verifyEventChain($grpc.ServiceCall call, $1.Empty request);

lib/src/generated/fai/v1/hub.pbjson.dart

@@ -143,6 +143,7 @@ const CapabilityEntry$json = {
     {'1': 'version', '3': 2, '4': 1, '5': 9, '10': 'version'},
     {'1': 'module_name', '3': 3, '4': 1, '5': 9, '10': 'moduleName'},
     {'1': 'module_version', '3': 4, '4': 1, '5': 9, '10': 'moduleVersion'},
+    {'1': 'kind', '3': 5, '4': 1, '5': 9, '10': 'kind'},
   ],
 };
 
@@ -150,7 +151,8 @@ const CapabilityEntry$json = {
 final $typed_data.Uint8List capabilityEntryDescriptor = $convert.base64Decode(
     'Cg9DYXBhYmlsaXR5RW50cnkSHgoKY2FwYWJpbGl0eRgBIAEoCVIKY2FwYWJpbGl0eRIYCgd2ZX'
     'JzaW9uGAIgASgJUgd2ZXJzaW9uEh8KC21vZHVsZV9uYW1lGAMgASgJUgptb2R1bGVOYW1lEiUK'
-    'Dm1vZHVsZV92ZXJzaW9uGAQgASgJUg1tb2R1bGVWZXJzaW9u');
+    'Dm1vZHVsZV92ZXJzaW9uGAQgASgJUg1tb2R1bGVWZXJzaW9uEhIKBGtpbmQYBSABKAlSBGtpbm'
+    'Q=');
 
 @$core.Deprecated('Use moduleInfoRequestDescriptor instead')
 const ModuleInfoRequest$json = {
@@ -173,6 +175,7 @@ const ModuleInfoResponse$json = {
     {'1': 'provides', '3': 3, '4': 3, '5': 11, '6': '.fai.v1.CapabilityRef', '10': 'provides'},
     {'1': 'permissions', '3': 4, '4': 3, '5': 9, '10': 'permissions'},
     {'1': 'directory', '3': 5, '4': 1, '5': 9, '10': 'directory'},
+    {'1': 'accepts_mime', '3': 6, '4': 3, '5': 9, '10': 'acceptsMime'},
   ],
 };
 
@@ -181,7 +184,7 @@ final $typed_data.Uint8List moduleInfoResponseDescriptor = $convert.base64Decode
     'ChJNb2R1bGVJbmZvUmVzcG9uc2USEgoEbmFtZRgBIAEoCVIEbmFtZRIYCgd2ZXJzaW9uGAIgAS'
     'gJUgd2ZXJzaW9uEjEKCHByb3ZpZGVzGAMgAygLMhUuZmFpLnYxLkNhcGFiaWxpdHlSZWZSCHBy'
     'b3ZpZGVzEiAKC3Blcm1pc3Npb25zGAQgAygJUgtwZXJtaXNzaW9ucxIcCglkaXJlY3RvcnkYBS'
-    'ABKAlSCWRpcmVjdG9yeQ==');
+    'ABKAlSCWRpcmVjdG9yeRIhCgxhY2NlcHRzX21pbWUYBiADKAlSC2FjY2VwdHNNaW1l');
 
 @$core.Deprecated('Use checkPermissionRequestDescriptor instead')
 const CheckPermissionRequest$json = {
@@ -532,6 +535,94 @@ final $typed_data.Uint8List fetchModuleDocsResponseDescriptor = $convert.base64D
     'ChdGZXRjaE1vZHVsZURvY3NSZXNwb25zZRIdCgplcnJvcl9raW5kGAEgASgJUgllcnJvcktpbm'
     'QSEgoEdGV4dBgCIAEoCVIEdGV4dBIdCgpzb3VyY2VfdXJsGAMgASgJUglzb3VyY2VVcmw=');
 
+@$core.Deprecated('Use getInstalledModuleDocsRequestDescriptor instead')
+const GetInstalledModuleDocsRequest$json = {
+  '1': 'GetInstalledModuleDocsRequest',
+  '2': [
+    {'1': 'name', '3': 1, '4': 1, '5': 9, '10': 'name'},
+    {'1': 'locale', '3': 2, '4': 1, '5': 9, '10': 'locale'},
+  ],
+};
+
+/// Descriptor for `GetInstalledModuleDocsRequest`. Decode as a `google.protobuf.DescriptorProto`.
+final $typed_data.Uint8List getInstalledModuleDocsRequestDescriptor = $convert.base64Decode(
+    'Ch1HZXRJbnN0YWxsZWRNb2R1bGVEb2NzUmVxdWVzdBISCgRuYW1lGAEgASgJUgRuYW1lEhYKBm'
+    'xvY2FsZRgCIAEoCVIGbG9jYWxl');
+
+@$core.Deprecated('Use getInstalledModuleDocsResponseDescriptor instead')
+const GetInstalledModuleDocsResponse$json = {
+  '1': 'GetInstalledModuleDocsResponse',
+  '2': [
+    {'1': 'text', '3': 1, '4': 1, '5': 9, '10': 'text'},
+    {'1': 'source_path', '3': 2, '4': 1, '5': 9, '10': 'sourcePath'},
+    {'1': 'not_installed', '3': 3, '4': 1, '5': 8, '10': 'notInstalled'},
+  ],
+};
+
+/// Descriptor for `GetInstalledModuleDocsResponse`. Decode as a `google.protobuf.DescriptorProto`.
+final $typed_data.Uint8List getInstalledModuleDocsResponseDescriptor = $convert.base64Decode(
+    'Ch5HZXRJbnN0YWxsZWRNb2R1bGVEb2NzUmVzcG9uc2USEgoEdGV4dBgBIAEoCVIEdGV4dBIfCg'
+    'tzb3VyY2VfcGF0aBgCIAEoCVIKc291cmNlUGF0aBIjCg1ub3RfaW5zdGFsbGVkGAMgASgIUgxu'
+    'b3RJbnN0YWxsZWQ=');
+
+@$core.Deprecated('Use invokePluginThemeRequestDescriptor instead')
+const InvokePluginThemeRequest$json = {
+  '1': 'InvokePluginThemeRequest',
+  '2': [
+    {'1': 'capability', '3': 1, '4': 1, '5': 9, '10': 'capability'},
+    {'1': 'brightness', '3': 2, '4': 1, '5': 9, '10': 'brightness'},
+  ],
+};
+
+/// Descriptor for `InvokePluginThemeRequest`. Decode as a `google.protobuf.DescriptorProto`.
+final $typed_data.Uint8List invokePluginThemeRequestDescriptor = $convert.base64Decode(
+    'ChhJbnZva2VQbHVnaW5UaGVtZVJlcXVlc3QSHgoKY2FwYWJpbGl0eRgBIAEoCVIKY2FwYWJpbG'
+    'l0eRIeCgpicmlnaHRuZXNzGAIgASgJUgpicmlnaHRuZXNz');
+
+@$core.Deprecated('Use invokePluginTranslateRequestDescriptor instead')
+const InvokePluginTranslateRequest$json = {
+  '1': 'InvokePluginTranslateRequest',
+  '2': [
+    {'1': 'capability', '3': 1, '4': 1, '5': 9, '10': 'capability'},
+    {'1': 'text', '3': 2, '4': 1, '5': 9, '10': 'text'},
+    {'1': 'from_locale', '3': 3, '4': 1, '5': 9, '10': 'fromLocale'},
+    {'1': 'to_locale', '3': 4, '4': 1, '5': 9, '10': 'toLocale'},
+  ],
+};
+
+/// Descriptor for `InvokePluginTranslateRequest`. Decode as a `google.protobuf.DescriptorProto`.
+final $typed_data.Uint8List invokePluginTranslateRequestDescriptor = $convert.base64Decode(
+    'ChxJbnZva2VQbHVnaW5UcmFuc2xhdGVSZXF1ZXN0Eh4KCmNhcGFiaWxpdHkYASABKAlSCmNhcG'
+    'FiaWxpdHkSEgoEdGV4dBgCIAEoCVIEdGV4dBIfCgtmcm9tX2xvY2FsZRgDIAEoCVIKZnJvbUxv'
+    'Y2FsZRIbCgl0b19sb2NhbGUYBCABKAlSCHRvTG9jYWxl');
+
+@$core.Deprecated('Use invokePluginTranslateResponseDescriptor instead')
+const InvokePluginTranslateResponse$json = {
+  '1': 'InvokePluginTranslateResponse',
+  '2': [
+    {'1': 'translated', '3': 1, '4': 1, '5': 9, '10': 'translated'},
+  ],
+};
+
+/// Descriptor for `InvokePluginTranslateResponse`. Decode as a `google.protobuf.DescriptorProto`.
+final $typed_data.Uint8List invokePluginTranslateResponseDescriptor = $convert.base64Decode(
+    'Ch1JbnZva2VQbHVnaW5UcmFuc2xhdGVSZXNwb25zZRIeCgp0cmFuc2xhdGVkGAEgASgJUgp0cm'
+    'Fuc2xhdGVk');
+
+@$core.Deprecated('Use invokePluginThemeResponseDescriptor instead')
+const InvokePluginThemeResponse$json = {
+  '1': 'InvokePluginThemeResponse',
+  '2': [
+    {'1': 'brightness', '3': 1, '4': 1, '5': 9, '10': 'brightness'},
+    {'1': 'tokens', '3': 2, '4': 3, '5': 13, '10': 'tokens'},
+  ],
+};
+
+/// Descriptor for `InvokePluginThemeResponse`. Decode as a `google.protobuf.DescriptorProto`.
+final $typed_data.Uint8List invokePluginThemeResponseDescriptor = $convert.base64Decode(
+    'ChlJbnZva2VQbHVnaW5UaGVtZVJlc3BvbnNlEh4KCmJyaWdodG5lc3MYASABKAlSCmJyaWdodG'
+    '5lc3MSFgoGdG9rZW5zGAIgAygNUgZ0b2tlbnM=');
+
 @$core.Deprecated('Use listApprovalsRequestDescriptor instead')
 const ListApprovalsRequest$json = {
   '1': 'ListApprovalsRequest',

lib/src/hub_client.dart

@@ -6,8 +6,10 @@
 
 import 'dart:typed_data';
 
-import 'package:grpc/grpc.dart';
+import 'package:grpc/grpc_connection_interface.dart';
 
+import 'channel_factory_io.dart'
+    if (dart.library.html) 'channel_factory_web.dart' as channel_factory;
 import 'generated/fai/v1/common.pb.dart' as pb_common;
 import 'generated/fai/v1/hub.pb.dart' as pb;
 import 'generated/fai/v1/hub.pbgrpc.dart' as grpc_hub;
@@ -59,6 +61,9 @@ typedef ClearEventLogResponse = pb.ClearEventLogResponse;
 typedef DaemonPathsResponse = pb.DaemonPathsResponse;
 typedef UninstallModuleResponse = pb.UninstallModuleResponse;
 typedef FetchModuleDocsResponse = pb.FetchModuleDocsResponse;
+typedef GetInstalledModuleDocsResponse = pb.GetInstalledModuleDocsResponse;
+typedef InvokePluginThemeResponse = pb.InvokePluginThemeResponse;
+typedef InvokePluginTranslateResponse = pb.InvokePluginTranslateResponse;
 typedef ListMcpClientsResponse = pb.ListMcpClientsResponse;
 typedef McpClientStatus = pb.McpClientStatus;
 typedef McpClientConfigEntry = pb.McpClientConfigEntry;
@@ -75,9 +80,15 @@ typedef SubmitResponse = pb.SubmitResponse;
 
 /// Typed client for the F∆I Hub gRPC surface. Construct once,
 /// reuse for the process lifetime, call [close] on shutdown.
+///
+/// The channel type is picked at compile time:
+///   * native targets → plain HTTP/2 gRPC via [ClientChannel].
+///   * web targets    → HTTP/1.1 gRPC-Web via [GrpcWebClientChannel].
+///                       Requires the hub to be running with the
+///                       `tonic-web` layer enabled.
 class HubClient {
   final HubEndpoint endpoint;
-  final ClientChannel _channel;
+  final ClientChannelBase _channel;
   final grpc_hub.HubClient _hub;
   final grpc_hub.HubAdminClient _admin;
 
@@ -86,17 +97,7 @@ class HubClient {
         _admin = grpc_hub.HubAdminClient(_channel);
 
   factory HubClient({HubEndpoint endpoint = const HubEndpoint()}) {
-    final channel = ClientChannel(
+    return HubClient._(endpoint, channel_factory.createChannel(endpoint));
-      endpoint.host,
-      port: endpoint.port,
-      options: ChannelOptions(
-        credentials: endpoint.secure
-            ? const ChannelCredentials.secure()
-            : const ChannelCredentials.insecure(),
-        idleTimeout: const Duration(minutes: 5),
-      ),
-    );
-    return HubClient._(endpoint, channel);
   }
 
   /// Liveness probe. Returns true when the hub responds with
@@ -240,6 +241,10 @@ class HubClient {
   /// when set, so Studio doesn't have to handle credentials.
   /// Errors come back inside [FetchModuleDocsResponse.errorKind]
   /// (not as exceptions) so the UI can render fallbacks.
+  ///
+  /// Deprecated: prefer [getInstalledModuleDocs], which reads
+  /// `MODULE.md`/`MODULE.<locale>.md` shipped inside the bundle.
+  @Deprecated('Use getInstalledModuleDocs (reads from bundle, no network)')
   Future<FetchModuleDocsResponse> fetchModuleDocs(
     String name, {
     String locale = '',
@@ -249,6 +254,80 @@ class HubClient {
     );
   }
 
+  /// Read the installed module's `MODULE.md` (or `MODULE.<locale>.md`)
+  /// from disk under `~/.fai/modules/<module>/`. No network. Works in
+  /// air-gapped installs. The response distinguishes three states via
+  /// [GetInstalledModuleDocsResponse.notInstalled] and an empty
+  /// [GetInstalledModuleDocsResponse.text]:
+  ///
+  /// - text non-empty → docs found, render them
+  /// - text empty + notInstalled=false → installed but bundle had
+  ///   no inline docs
+  /// - text empty + notInstalled=true → module is not installed
+  Future<GetInstalledModuleDocsResponse> getInstalledModuleDocs(
+    String name, {
+    String locale = '',
+  }) {
+    return _admin.getInstalledModuleDocs(
+      pb.GetInstalledModuleDocsRequest(name: name, locale: locale),
+    );
+  }
+
+  /// Invoke an installed Studio plugin's `theme` hook and
+  /// receive a Material 3 ColorScheme for the brightness
+  /// ("light" or "dark") the caller asked for.
+  ///
+  /// [capability] is the full Studio-plugin capability name
+  /// (e.g. "studio.theme.solarized"). [brightness] must be
+  /// "light" or "dark"; other values surface as
+  /// `INVALID_ARGUMENT` from the hub. A plugin that doesn't
+  /// recognise the brightness returns Declined, which the
+  /// hub maps to `FAILED_PRECONDITION` — Studio's
+  /// friendly-error mapper renders it with a recovery hint.
+  ///
+  /// The first end-to-end RPC of the Studio-plugin
+  /// subsystem; `translate` and `output-view` hooks get
+  /// their own methods once the matching Studio surfaces
+  /// ship.
+  Future<InvokePluginThemeResponse> invokePluginTheme({
+    required String capability,
+    required String brightness,
+  }) {
+    return _admin.invokePluginTheme(
+      pb.InvokePluginThemeRequest(
+        capability: capability,
+        brightness: brightness,
+      ),
+    );
+  }
+
+  /// Invoke an installed Studio plugin's `translate` hook and
+  /// receive translated text. [fromLocale] may be empty
+  /// (auto-detect); [toLocale] must be a BCP-47 code (the
+  /// host always knows the target).
+  ///
+  /// Errors surface as gRPC exceptions:
+  ///   * NOT_FOUND       — plugin not installed.
+  ///   * FAILED_PRECONDITION — plugin returned Declined or
+  ///                     Misconfigured (e.g. unreachable
+  ///                     LLM endpoint).
+  ///   * INTERNAL        — generic catch-all.
+  Future<InvokePluginTranslateResponse> invokePluginTranslate({
+    required String capability,
+    required String text,
+    required String toLocale,
+    String fromLocale = '',
+  }) {
+    return _admin.invokePluginTranslate(
+      pb.InvokePluginTranslateRequest(
+        capability: capability,
+        text: text,
+        fromLocale: fromLocale,
+        toLocale: toLocale,
+      ),
+    );
+  }
+
   /// List every configured MCP server with the last-discovery
   /// snapshot. Drives Studio's MCP-clients editor.
   Future<ListMcpClientsResponse> listMcpClients() {
@@ -489,27 +568,33 @@ class HubClient {
   /// flow that mixes text and binary inputs (e.g. extract
   /// taking a `document: bytes`) flows through one RPC:
   ///   * [textInputs] — string values wrapped as text Payloads
-  ///   * [fileInputs] — raw bytes wrapped as bytes Payloads,
+  ///   * [fileInputs] — raw bytes wrapped as bytes Payloads.
-  ///                     with `application/octet-stream` MIME
+  ///                     MIME type defaults to
-  ///                     type. Caller can override the MIME by
+  ///                     `application/octet-stream`; clients that
-  ///                     passing a [bytePayloads] entry instead.
+  ///                     know the real type pass it via
-  /// Both maps default to empty so existing text-only callers
+  ///                     [fileMimeTypes] (same key). Modules
+  ///                     typically gate on MIME — e.g.
+  ///                     `text.extract` rejects octet-stream — so
+  ///                     accurate types matter.
+  /// All maps default to empty so existing text-only callers
   /// are backward-compatible. Keys must not collide between
-  /// the maps; on collision the bytes-shaped entry wins (the
+  /// [textInputs] and [fileInputs]; on collision the bytes-shaped
-  /// less-common case is more likely to be the operator's
+  /// entry wins (the less-common case is more likely to be the
-  /// intent).
+  /// operator's intent).
   Future<SubmitResponse> runSavedFlow({
     required String name,
     Map<String, String> textInputs = const {},
     Map<String, Uint8List> fileInputs = const {},
+    Map<String, String> fileMimeTypes = const {},
   }) async {
     final req = pb.RunSavedFlowRequest()..name = name;
     for (final entry in textInputs.entries) {
       req.inputs[entry.key] = pb_common.Payload()..text = entry.value;
     }
     for (final entry in fileInputs.entries) {
+      final mime = fileMimeTypes[entry.key] ?? 'application/octet-stream';
       final bytes = pb_common.Bytes()
-        ..mimeType = 'application/octet-stream'
+        ..mimeType = mime
         ..data = entry.value;
       req.inputs[entry.key] = pb_common.Payload()..bytes = bytes;
     }