feat(studio): Doctor + Modules localized + sparse-store federation nudge (v0.25.0)

Two threads.

Translation expansion: every visible string on the Doctor
page (section headers, status text, button labels, daemon-
control card, daemon-files panel, update banner) and the
Modules page (recent-activity strip, capabilities label,
uninstall dialog + toast) flips between DE and EN with the
sidebar toggle. Adds ~50 ARB keys split between
`app_en.arb` / `app_de.arb`. Pluralised + parametrised
strings (`{n} events verified`, `Running on {name}: {endpoint}`)
use the standard ICU placeholder syntax so future locales
slot in without code changes.

Sparse-store federation nudge: the Store page renders an
inline banner above the grid when the operator has zero
federated entries — single biggest store-fullness lever is
configuring an MCP server / n8n endpoint, so the banner
says exactly that and the button opens Settings straight
to the editor. Banner dismisses automatically the next
render after a federated entry appears.

Coverage stand for translation: Doctor + Modules + sidebar
+ page titles + nav + Cmd+K labels are bilingual. Settings
dialog, Approvals cards, Audit drilldown, MCP/n8n editors,
Store search hint + filter chips remain English-literal.
The infrastructure (ARB plumbing, generator hookup,
locale-notifier) means each follow-up surface is a
one-line ARB edit + one call-site swap.

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

lib/l10n/app_de.arb

@@ -61,6 +61,9 @@
   "@storeNResults": {
     "placeholders": { "n": { "type": "int" } }
   },
+  "storeFederationNudgeTitle": "Mehr Capabilities?",
+  "storeFederationNudgeBody": "MCP-Server oder n8n-Endpunkt unter Einstellungen → MCP-Clients / N8N-Endpunkte konfigurieren. Entdeckte Tools und Workflows tauchen hier als `mcp.<server>.<tool>`- und `n8n.<endpoint>.<workflow>`-Capabilities auf — jeder Anthropic-/Community-MCP-Server bringt mehrere auf einmal.",
+  "storeFederationNudgeButton": "Einstellungen öffnen",
 
   "auditTitle": "Protokoll",
   "auditNoEvents": "Noch keine Ereignisse",
@@ -68,7 +71,32 @@
 
   "modulesTitle": "Module",
   "modulesNoneTitle": "Noch keine Module",
+  "modulesNoneHint": "`fai install <capability-name>` ausführen oder ~/.fai/modules/ prüfen.",
+  "modulesReloadTooltip": "Aktualisieren",
   "modulesRecentActivity": "LETZTE AKTIVITÄT",
+  "modulesRecentActivityHint": "letzte {n} install/uninstall-Ereignisse aus dem Audit-Log",
+  "@modulesRecentActivityHint": { "placeholders": { "n": { "type": "int" } } },
+  "modulesActivityInstalled": "installiert",
+  "modulesActivityUninstalled": "deinstalliert",
+  "modulesCapabilitiesLabel": "Capabilities",
+  "modulesUninstallTitle": "Modul deinstallieren?",
+  "modulesUninstallBody": "Entfernt {name} v{version} von diesem Hub. Flows, die es verwenden, schlagen beim nächsten Lauf fehl. Ein `module.uninstalled`-Audit-Event wird festgehalten.",
+  "@modulesUninstallBody": {
+    "placeholders": {
+      "name": { "type": "String" },
+      "version": { "type": "String" }
+    }
+  },
+  "modulesUninstalledToast": "{name} v{version} deinstalliert.",
+  "@modulesUninstalledToast": {
+    "placeholders": {
+      "name": { "type": "String" },
+      "version": { "type": "String" }
+    }
+  },
+  "modulesUninstallFailed": "Deinstallation fehlgeschlagen: {error}",
+  "@modulesUninstallFailed": { "placeholders": { "error": { "type": "String" } } },
+  "modulesUninstalling": "Wird deinstalliert…",
 
   "approvalsTitle": "Freigaben",
   "approvalsTabPending": "Offen",
@@ -77,6 +105,73 @@
   "approvalsInboxHint": "Alles erledigt. Neue `system.approval@^0`-Schritte landen automatisch hier.",
 
   "doctorTitle": "Diagnose",
+  "doctorRecheckTooltip": "Erneut prüfen",
+  "doctorEventLogSection": "Audit-Log",
+  "doctorModulesApprovalsSection": "Module & Freigaben",
+  "doctorHostServicesSection": "Host-Dienste",
+  "doctorDaemonFilesSection": "Daemon-Dateien",
+  "doctorDaemonControlSection": "Daemon-Steuerung",
+  "doctorChainIntact": "Hash-Chain intakt",
+  "doctorChainIntactDetail": "{n} Ereignisse · prev_event_sha256 lückenlos verifiziert",
+  "@doctorChainIntactDetail": { "placeholders": { "n": { "type": "int" } } },
+  "doctorChainTampered": "Manipulation erkannt",
+  "doctorChainTamperedDetail": "{verified} von {total} verifiziert vor Mismatch bei {id}",
+  "@doctorChainTamperedDetail": {
+    "placeholders": {
+      "verified": { "type": "int" },
+      "total": { "type": "int" },
+      "id": { "type": "String" }
+    }
+  },
+  "doctorChainPillOk": "WORM-1",
+  "doctorChainPillTamper": "MANIPULIERT",
+  "doctorVerifyNow": "Jetzt prüfen",
+  "doctorRestart": "Neustart",
+  "doctorStart": "Starten",
+  "doctorStop": "Stoppen",
+  "doctorStatusAction": "Status",
+  "doctorRunningOn": "Läuft auf {name}: {endpoint}",
+  "@doctorRunningOn": {
+    "placeholders": {
+      "name": { "type": "String" },
+      "endpoint": { "type": "String" }
+    }
+  },
+  "doctorStoppedOn": "{name}-Daemon gestoppt",
+  "@doctorStoppedOn": { "placeholders": { "name": { "type": "String" } } },
+  "doctorStatusUnknown": "Daemon-Status: …",
+  "doctorPillRunning": "läuft",
+  "doctorPillStopped": "gestoppt",
+  "doctorDaemonControlHint": "Studio ruft das Platform-Binary auf — entspricht `fai daemon …`, sodass CLI und UI im Gleichschritt bleiben.",
+  "doctorDaemonControlWorking": "Wird ausgeführt…",
+  "doctorPathLog": "Log",
+  "doctorPathConfig": "Konfig",
+  "doctorPathDb": "Audit-DB",
+  "doctorPathModules": "Module-Verzeichnis",
+  "doctorPathFlows": "Flow-Verzeichnis",
+  "doctorPathPid": "PID-Datei",
+  "doctorPathsEmpty": "Daemon hat keine Datei-Pfade gemeldet. Hub aktualisieren via `fai daemon restart`.",
+  "doctorOpenError": "Konnte nicht öffnen: {detail}",
+  "@doctorOpenError": { "placeholders": { "detail": { "type": "String" } } },
+  "doctorUpdateAvailable": "Update verfügbar — {version}",
+  "@doctorUpdateAvailable": { "placeholders": { "version": { "type": "String" } } },
+  "doctorUpdateBody": "Kanal {channel} bietet jetzt {version}. Per Button anwenden — Studio ruft `fai update apply --channel {channel}` auf.",
+  "@doctorUpdateBody": {
+    "placeholders": {
+      "channel": { "type": "String" },
+      "version": { "type": "String" }
+    }
+  },
+  "doctorUpdateUnreachable": "Release-Host nicht erreichbar",
+  "doctorUpdateUnreachableBody": "Release-Feed für {channel} konnte nicht erreicht werden.",
+  "@doctorUpdateUnreachableBody": { "placeholders": { "channel": { "type": "String" } } },
+  "doctorReleaseNotes": "Notes: {url}",
+  "@doctorReleaseNotes": { "placeholders": { "url": { "type": "String" } } },
+  "doctorPillNew": "neu",
+  "doctorPillOffline": "offline",
+  "doctorApplyUpdate": "Update anwenden",
+  "doctorApplying": "Wird angewendet…",
+  "doctorApplyDone": "Update angewendet. Studio neu starten, um die neue Daemon-Version zu sehen.",
 
   "mcpHeader": "MCP-CLIENTS",
   "mcpHint": "Externe MCP-Server bringen ihre Tools als `mcp.<server>.<tool>` Capabilities ein. Einmal konfigurieren, im Store sichtbar.",