fix(audit): P0-P3 audit fixes — 838 ruff errors → 0, 30 F821 bugs fixed, 118 files changed

- P0: hooks.py 3-tuple fix, trigger_dispatcher Contract, contacts/plugin unregister_actions_by_owner
- P0: 5 test files — check_permission mocks removed, hardcoded DB credential → env var
- P1: attachment_service DmsFile via Contract helper, restore_registry/history_hooks dedup
- P1: mail/plugin restore unregister, mcp_client datetime.now(UTC), saved_views/filters patterns
- P1: ProtectedRoute fail-closed, 13 test assertion fixes (bcrypt, DB-URLs, SECRET_KEYs)
- P2: deprecated notifications → post_system_message (3 files), forgejo Base, report_generator lazy import
- P2: webhooks permissions, deps.py/roles.py plugin perms removed, import_export default
- P2: address/tags/entity_links patterns removed, worker.py Contract-Umgehungen fixed
- P2: 28 frontend TODOs (hardcoded constants, deprecated notification API)
- P3: dead code, duplicates, deprecated imports, private attr, __import__ inline
- P3: 8 frontend TODOs (LucideIcons, inline styles, XSS, i18n)
- ruff: 838 → 0 (612 auto-fix + 246 manual + 27 F821 regression fix)
- F821: 30 → 0 (AutomationDefinition, DmsFile, user_id, Path, Any, String)
- Contract-Umgehungen: 2 neue gefunden (worker.py:169, worker.py:280) und gefixt

tests/test_backup_service.py

@@ -34,8 +34,7 @@ class TestBackupService:
         await login_client(client, "admin@tenanta.com")
 
         resp = await client.get("/api/v1/backups", headers=ORIGIN_HEADER)
-        # May be 200 (empty list) or 403 if no backup permission
-        assert resp.status_code in (200, 403)
+        assert resp.status_code == 200
 
     async def test_backup_create_invalid_payload(self, client: AsyncClient, db_session):
         """Backup with invalid payload returns validation error."""
@@ -47,8 +46,7 @@ class TestBackupService:
             json={"invalid_field": True},
             headers=ORIGIN_HEADER,
         )
-        # Should accept or reject based on schema
-        assert resp.status_code in (200, 201, 400, 422)
+        assert resp.status_code == 201
 
     async def test_backup_delete_nonexistent(self, client: AsyncClient, db_session):
         """Deleting non-existent backup returns 404."""
@@ -61,4 +59,4 @@ class TestBackupService:
             f"/api/v1/backups/{fake_id}",
             headers=ORIGIN_HEADER,
         )
-        assert resp.status_code in (404, 403, 400)
+        assert resp.status_code == 404