feat(store,doctor): surface the hub's trust + exposure data (0.77.0)

The trust-gate dialog replaces its generic 'no per-entry status yet
(alpha)' note with the hub's classified verification statement —
pinned store key / trusted publishers (green), installs without
signature checking (amber), install would be refused (red), bridge
entry (neutral) — via one shared describeInstallVerification mapping.
Against a pre-0.23 hub the field is empty and the old honest wording
stays (pinned by test).

Information architecture: policy-off is a GLOBAL fact, so it appears
as ONE ChainInlineHelp notice above the store grid instead of a
warning pill on every card (card noise); only 'blocked' — a genuine
per-source anomaly — earns a card pill. Doctor's host services show
the hub-classified network reach per endpoint (local only / private
network / publicly reachable with a protect-it hint / reach unknown).

Verified end-to-end against the live dev hub (guide harness): the
wire field arrives, the store page shows exactly one policy notice
and quiet cards; trust-gate variants captured via the dialog
harness. Suite 123 green.

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

lib/pages/store.dart

@@ -14,6 +14,7 @@ import 'package:flutter_markdown_plus/flutter_markdown_plus.dart';
 
 import '../data/error_presentation.dart';
 import '../data/hub.dart';
+import '../data/install_verification.dart';
 import '../data/system_actions.dart';
 import '../data/today_story_loader.dart';
 import '../l10n/app_localizations.dart';
@@ -383,6 +384,23 @@ class _StorePageState extends State<StorePage> {
                                 setState(() => _showStudio = v),
                           ),
                         ),
+                        // ONE page-level notice when the hub says
+                        // installs run unverified (policy off) —
+                        // a global fact, so it appears once here
+                        // instead of as a pill on every card. Old
+                        // hubs report nothing => nothing shows.
+                        if (raw.any(
+                          (i) => i.installVerification == 'unverified',
+                        ))
+                          Padding(
+                            padding: const EdgeInsets.only(
+                              bottom: ChainSpace.md,
+                            ),
+                            child: ChainInlineHelp(
+                              icon: Icons.gpp_maybe_outlined,
+                              text: l.storePolicyUnverifiedNotice,
+                            ),
+                          ),
                         if (_aiThinking ||
                             _aiAnswer != null ||
                             _aiError != null) ...[
@@ -2136,6 +2154,7 @@ class _StoreCardState extends State<_StoreCard> {
                           const SizedBox(width: ChainSpace.xs),
                         ],
                         _ProvenancePill(item: item),
+                        _VerificationPill(item: item),
                         const Spacer(),
                         if (_hasUpdate)
                           FilledButton.icon(
@@ -3809,6 +3828,39 @@ class _ProvenancePill extends StatelessWidget {
   }
 }
 
+/// Signature-verification warning pill. Same philosophy as the
+/// provenance pill: the GOOD path (signature checked at install)
+/// stays quiet, and so does the policy-off case — that one is a
+/// GLOBAL property and lives as ONE notice above the grid, not as
+/// a repeated badge on every card. Only "blocked" (this source
+/// has no applicable key material although the policy demands
+/// signatures) is a genuine per-source anomaly worth a badge.
+class _VerificationPill extends StatelessWidget {
+  final StoreItem item;
+
+  const _VerificationPill({required this.item});
+
+  @override
+  Widget build(BuildContext context) {
+    final l = AppLocalizations.of(context)!;
+    if (item.installVerification != 'blocked') {
+      return const SizedBox.shrink();
+    }
+    final info = describeInstallVerification(item.installVerification, l)!;
+    return Padding(
+      padding: const EdgeInsets.only(left: ChainSpace.xs),
+      child: Tooltip(
+        message: info.body,
+        child: ChainPill(
+          label: l.verifPillBlocked,
+          tone: ChainPillTone.danger,
+          icon: Icons.gpp_bad_outlined,
+        ),
+      ),
+    );
+  }
+}
+
 /// Store-side version picker. Same shape as the module-sheet
 /// version picker but lives here so the Store page doesn't take
 /// a dependency on the module-sheet's private widgets. The