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

tests/test_m6_miniapp_hosts.py

@@ -0,0 +1,171 @@
+"""M6 — further hosts tests.
+
+Windows host: MiniApps open in floating windows (frontend — covered by
+vitest). AI agent host: the core tool ``send_miniapp`` lets agents embed a
+MiniApp as an output block in their chat (approval_request precedent from
+agent_loop), permission-checked fail-closed against the calling user.
+"""
+
+from __future__ import annotations
+
+import inspect
+
+import pytest
+
+from app.ai.tool_registry import get_tool_registry
+
+
+@pytest.fixture(autouse=True)
+def _clean_registries():
+    from app.plugins.miniapp_registry import reset_miniapp_registry
+
+    reset_miniapp_registry()
+    yield
+    reset_miniapp_registry()
+    get_tool_registry()._tools.pop("send_miniapp", None)
+
+
+def _ctx(**overrides) -> dict:
+    # db is always present in production tool contexts (agent_loop passes
+    # the session); a plain object() stands in for tests where the handler
+    # only forwards it to mocked collaborators.
+    ctx = {
+        "db": object(),
+        "tenant_id": "00000000-0000-0000-0000-000000000001",
+        "user_id": "00000000-0000-0000-0000-000000000002",
+        "agent_name": "TestAgent",
+    }
+    ctx.update(overrides)
+    return ctx
+
+
+class TestSendMiniAppToolRegistration:
+    def test_register_registers_tool(self):
+        from app.ai.miniapp_tools import register_miniapp_tools
+
+        register_miniapp_tools()
+        tool = get_tool_registry().get("send_miniapp")
+        assert tool is not None
+        assert tool.plugin_name == "system"
+        assert tool.category == "ui"
+        # App id is the only required parameter
+        props = tool.parameters.get("properties", {})
+        assert "app_id" in props
+        assert tool.parameters.get("required") == ["app_id"]
+
+
+class TestSendMiniAppHandler:
+    async def test_unknown_app_returns_error(self):
+        from app.ai.miniapp_tools import _send_miniapp_handler
+
+        result = await _send_miniapp_handler({"app_id": "no_such_app"}, _ctx())
+        assert "not found" in result.lower()
+
+    async def test_unknown_app_never_touches_chat(self, monkeypatch):
+        """Fail-closed: unknown app must not post anything anywhere."""
+        from app.ai import miniapp_tools
+
+        called = []
+        monkeypatch.setattr(
+            miniapp_tools, "_get_komm_contract", lambda: (_ for _ in ()).throw(AssertionError("must not be called"))
+        )
+        from app.ai.miniapp_tools import _send_miniapp_handler
+
+        await _send_miniapp_handler({"app_id": "nope"}, _ctx())
+        assert called == []
+
+    async def test_permission_denied_returns_error(self, monkeypatch):
+        """User without the app permission cannot make the agent send it."""
+        from app.ai import miniapp_tools
+        from app.plugins.miniapp_registry import get_miniapp_registry
+
+        get_miniapp_registry().register(
+            app_id="tasks_widget", name="Tasks", plugin_name="tasks",
+            permission="tasks:read", component="@/components/x",
+        )
+
+        async def fake_resolve(db, user_id, tenant_id):
+            return {"permissions": set(), "denied": set(), "is_system_admin": False}
+
+        monkeypatch.setattr(miniapp_tools, "resolve_permissions", fake_resolve)
+        monkeypatch.setattr(
+            miniapp_tools, "_get_komm_contract", lambda: (_ for _ in ()).throw(AssertionError("must not post"))
+        )
+        from app.ai.miniapp_tools import _send_miniapp_handler
+
+        result = await _send_miniapp_handler({"app_id": "tasks_widget"}, _ctx())
+        assert "permission" in result.lower()
+
+    async def test_posts_miniapp_block_to_agent_room(self, monkeypatch):
+        """Happy path: block with app_id + settings lands in the agent room."""
+        from app.ai import miniapp_tools
+        from app.plugins.miniapp_registry import get_miniapp_registry
+
+        get_miniapp_registry().register(
+            app_id="open_widget", name="Open", plugin_name="test",
+            permission="", component="@/components/x",
+        )
+
+        async def fake_resolve(db, user_id, tenant_id):
+            return {"permissions": {"*:*"}, "denied": set(), "is_system_admin": True}
+
+        posted: list[dict] = []
+
+        class FakeKomm:
+            async def find_locked_room_id(self, db, tenant_id, plugin_name, title):
+                assert plugin_name == "automation"
+                assert title == "Agent: TestAgent"
+                return "conv-123"
+
+            async def send_message(self, **kwargs):
+                posted.append(kwargs)
+
+        monkeypatch.setattr(miniapp_tools, "resolve_permissions", fake_resolve)
+        monkeypatch.setattr(miniapp_tools, "_get_komm_contract", lambda: FakeKomm())
+        from app.ai.miniapp_tools import _send_miniapp_handler
+
+        result = await _send_miniapp_handler(
+            {"app_id": "open_widget", "settings": {"limit": 5}}, _ctx()
+        )
+        assert "sent" in result.lower() or "success" in result.lower()
+        assert len(posted) == 1
+        msg = posted[0]
+        assert msg["conversation_id"] == "conv-123"
+        assert msg["sender_type"] == "agent"
+        blocks = msg["blocks"]
+        assert len(blocks) == 1
+        assert blocks[0]["block_type"] == "miniapp"
+        assert blocks[0]["block_data"]["app_id"] == "open_widget"
+        assert blocks[0]["block_data"]["config"] == {"limit": 5}
+
+    async def test_missing_room_degrades_gracefully(self, monkeypatch):
+        """No agent chat room -> informative result, no crash."""
+        from app.ai import miniapp_tools
+        from app.plugins.miniapp_registry import get_miniapp_registry
+
+        get_miniapp_registry().register(
+            app_id="open_widget", name="Open", plugin_name="test", permission=""
+        )
+
+        async def fake_resolve(db, user_id, tenant_id):
+            return {"permissions": set(), "denied": set(), "is_system_admin": True}
+
+        class FakeKomm:
+            async def find_locked_room_id(self, db, tenant_id, plugin_name, title):
+                return None
+
+        monkeypatch.setattr(miniapp_tools, "resolve_permissions", fake_resolve)
+        monkeypatch.setattr(miniapp_tools, "_get_komm_contract", lambda: FakeKomm())
+        from app.ai.miniapp_tools import _send_miniapp_handler
+
+        result = await _send_miniapp_handler({"app_id": "open_widget"}, _ctx())
+        assert "room" in result.lower() or "chat" in result.lower()
+
+
+class TestAgentLoopContext:
+    def test_tool_context_carries_agent_name(self):
+        """agent_loop must pass the agent's name so tools can find the room."""
+        from app.ai import agent_loop
+
+        src = inspect.getsource(agent_loop)
+        assert '"agent_name"' in src, "tool_context must include agent_name"