feat(M6): Weitere Hosts — MiniApps in Fenstern + AI-Agenten-Ausgabe-Bloecke (#364)

- Windows-Host: openMiniAppWindow-Helper + MiniAppWindowContent (windowStore);
  Oeffnen-Buttons im Chat-Block (MiniAppBlock) und Dashboard-Widget
- AI-Agenten-Host: Core-Tool send_miniapp (app/ai/miniapp_tools.py) —
  miniapp-Block in Agent-Chat (approval_request-Praezedenz), Permission
  fail-closed gegen aufrufenden User pro App; Registrierung im lifespan
- agent_loop: tool_context + agent_name (Raum-Aufloesung)
- Fix: MiniAppBlock nutzt useMiniapps (component-Feld) statt Legacy /comm/miniapps
- Tests: M6 7/7 (TDD rot->gruen), Backend-Regression 57/57, Vitest 26/26
  (4 neue Window-Tests), tsc clean, build OK

frontend/src/components/comm/blocks/MiniAppBlock.tsx

@@ -1,42 +1,36 @@
-import React, { useState, useEffect } from 'react';
+import React from 'react';
+import { useTranslation } from 'react-i18next';
 import type { MessageBlock } from '@/store/commStore';
-import { AppWindow, Loader2 } from 'lucide-react';
-import { apiClient } from '@/api/client';
+import { AppWindow, ExternalLink, Loader2 } from 'lucide-react';
+import { useMiniapps, type MiniAppDef } from '@/api/miniapps';
+import { MiniAppWindowContent } from '@/components/dashboard/MiniAppWindowContent';
+import { openMiniAppWindow } from '@/components/dashboard/openMiniAppWindow';
 
 interface MiniAppBlockProps {
   block: MessageBlock;
 }
 
-interface MiniAppDef {
-  app_id: string;
-  name: string;
-  icon: string;
-  description: string;
-  plugin_name: string;
-  render_schema: Record<string, any>;
-}
-
 const MiniAppBlock: React.FC<MiniAppBlockProps> = ({ block }) => {
+  const { t } = useTranslation();
   const { app_id, config } = block.block_data;
-  const [appDef, setAppDef] = useState<MiniAppDef | null>(null);
-  const [loading, setLoading] = useState(false);
+  // M6: universal registry endpoint (carries component/permission fields;
+  // the legacy /comm/miniapps list never did, hiding the window button)
+  const { data: miniappsData, isLoading: loading } = useMiniapps();
+  const appDef: MiniAppDef | null =
+    miniappsData?.items.find((a) => a.app_id === app_id) ?? null;
 
-  useEffect(() => {
-    if (!app_id) return;
-    setLoading(true);
-    apiClient.get('/comm/miniapps')
-      .then((res) => {
-        const apps: MiniAppDef[] = res.data || [];
-        const found = apps.find((a) => a.app_id === app_id);
-        setAppDef(found || null);
-      })
-      .catch(() => setAppDef(null))
-      .finally(() => setLoading(false));
-  }, [app_id]);
+  const canOpenInWindow = Boolean(appDef?.component);
+  const openInWindow = () =>
+    openMiniAppWindow({
+      appId: app_id || '',
+      def: appDef ?? undefined,
+      settings: (config as Record<string, unknown>) ?? {},
+      component: MiniAppWindowContent,
+    });
 
   const appId: string = app_id || 'Unbekannt';
   const hasConfig = config && typeof config === 'object' && Object.keys(config).length > 0;
-  const schema = appDef?.render_schema;
+  const schema = appDef?.render_schema as { fields?: { name: string; label?: string }[] } | undefined;
   const hasSchema = schema && Object.keys(schema).length > 0;
 
   if (loading) {
@@ -60,6 +54,18 @@ const MiniAppBlock: React.FC<MiniAppBlockProps> = ({ block }) => {
         {appDef?.plugin_name && (
           <span className="text-xs px-2 py-0.5 rounded-full bg-secondary-100 text-secondary-600">{appDef.plugin_name}</span>
         )}
+        {canOpenInWindow && (
+          <button
+            type="button"
+            onClick={openInWindow}
+            className="p-1.5 rounded hover:bg-secondary-100 text-secondary-400 hover:text-primary-600"
+            aria-label={t('dashboard.openInWindow')}
+            title={t('dashboard.openInWindow')}
+            data-testid={`miniapp-open-window-${app_id}`}
+          >
+            <ExternalLink className="w-4 h-4" aria-hidden="true" />
+          </button>
+        )}
       </div>
 
       {hasSchema && schema.fields && (