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/services/entity_history_service.py

@@ -3,7 +3,7 @@
 from __future__ import annotations
 
 import uuid
-from datetime import datetime, timezone
+from datetime import UTC, datetime
 from typing import Any
 
 from sqlalchemy import select
@@ -148,7 +148,6 @@ async def restore_from_history(
         return await config.special_handler(db, entity, action, snapshot, context)
 
     # Generic restore logic
-    from datetime import datetime, timezone
 
     if action == "delete":
         if entity is None:
@@ -176,7 +175,7 @@ async def restore_from_history(
     elif action == "create":
         if entity is None:
             raise ValueError("Entity not found for restore")
-        entity.deleted_at = datetime.now(timezone.utc)
+        entity.deleted_at = datetime.now(UTC)
         if hasattr(entity, "updated_by"):
             entity.updated_by = user_id
         await db.flush()
@@ -193,16 +192,7 @@ def _serialize_entity(entity: Any, entity_type: str) -> dict[str, Any]:
     """
     if entity_type == "contact":
         from app.services.contact_service import _serialize_contact_detail
-        from sqlalchemy.orm import selectinload
-        from app.models.contact import Contact
-        from sqlalchemy import select as sa_select
 
-        # Re-query with selectinload for contact_persons
-        q = (
-            sa_select(Contact)
-            .options(selectinload(Contact.contact_persons))
-            .where(Contact.id == entity.id)
-        )
         # This is called after flush, entity is still in session
         # but we need to reload with the relationship
         return _serialize_contact_detail(entity)
@@ -365,10 +355,11 @@ async def archive_old_history(
     GDPR compliance: after retention period, history snapshots are purged.
     Returns the number of archived entries.
     """
-    from datetime import datetime, timezone, timedelta
+    from datetime import timedelta
+
     from sqlalchemy import delete as sa_delete
 
-    cutoff = datetime.now(timezone.utc) - timedelta(days=days)
+    cutoff = datetime.now(UTC) - timedelta(days=days)
     stmt = sa_delete(EntityHistory).where(
         EntityHistory.tenant_id == tenant_id,
         EntityHistory.created_at < cutoff,