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

app/plugins/builtins/mcp_client/models.py

@@ -3,9 +3,9 @@
 from __future__ import annotations
 
 import uuid
-from datetime import datetime
+from datetime import UTC, datetime
 
-from sqlalchemy import Boolean, DateTime, ForeignKey, Index, String, Text
+from sqlalchemy import Boolean, DateTime, Index, String, Text
 from sqlalchemy.dialects.postgresql import UUID as PGUUID
 from sqlalchemy.orm import Mapped, mapped_column
 
@@ -32,5 +32,5 @@ class McpServerConfig(Base, TenantMixin, OwnedMixin):
     description: Mapped[str | None] = mapped_column(Text, nullable=True)
     last_connected_at: Mapped[datetime | None] = mapped_column(DateTime(timezone=True), nullable=True)
     created_by: Mapped[uuid.UUID | None] = mapped_column(PGUUID(as_uuid=True), nullable=True)
-    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=datetime.utcnow, nullable=False)
-    updated_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=datetime.utcnow, onupdate=datetime.utcnow, nullable=False)
+    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=datetime.now(UTC), nullable=False)
+    updated_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=datetime.now(UTC), onupdate=datetime.now(UTC), nullable=False)