feat(M5): Plugin-MiniApps — dms, mail, wiki, graph_rag, automation (#363)

- 5 Manifest-Beiträge (MiniAppContribution): dms_folders (dms:read), mail_unread (mail:read), wiki_recent (wiki:read), graph_overview (graph:read), automation_status (automation:read) — je settings_schema max_items, order 60-100
- 5 Frontend-Widgets auf bestehenden API-Clients (keine neuen Backend-Endpoints): DmsFoldersWidget, MailUnreadWidget, WikiRecentWidget, GraphOverviewWidget, AutomationStatusWidget
- MiniAppHost-Registry +5; tsc clean, build OK
- Tests: M5 7/7 (TDD rot->gruen), Backend-Regression 53/53, Vitest 22/22

app/plugins/builtins/dms/plugin.py

@@ -6,6 +6,7 @@ from app.plugins.base import BasePlugin
 from app.plugins.manifest import (
     FrontendMenuItem,
     FrontendPageRoute,
+    MiniAppContribution,
     PluginManifest,
     PluginRouteDef,
 )
@@ -29,6 +30,25 @@ class DmsPlugin(BasePlugin):
         ],
         events=[],
         migrations=["0001_initial.sql"],
+        miniapps=[
+            MiniAppContribution(
+                app_id="dms_folders",
+                name="DMS-Ordner",
+                icon="FolderOpen",
+                description="Ordnerübersicht des Dokumentenmanagements mit Dateizählern.",
+                permission="dms:read",
+                settings_schema={
+                    "fields": [
+                        {"name": "max_items", "label": "Max. Ordner", "type": "number", "default": 6},
+                    ]
+                },
+                col_span=2,
+                row_span=1,
+                hosts=["chat", "dashboard", "window"],
+                component="@/components/dashboard/DmsFoldersWidget",
+                order=60,
+            ),
+        ],
         permissions=[
             "dms:read",
             "dms:write",