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/tasks/jobs.py

@@ -3,7 +3,6 @@
 from __future__ import annotations
 
 import logging
-from datetime import datetime, timezone
 
 from app.core.db import get_session_factory
 
@@ -16,11 +15,12 @@ async def tasks_due_reminder(ctx: dict) -> None:
     Runs daily at 8:00 via cron. Finds all non-done tasks with due_date <= now
     and creates a notification for the assigned user.
     """
-    from app.plugins.builtins.tasks.services import get_due_tasks
-    from app.models.tenant import Tenant
-    from app.core.notifications import create_notification
     from sqlalchemy import select
 
+    from app.core.notifications import create_notification
+    from app.models.tenant import Tenant
+    from app.plugins.builtins.tasks.services import get_due_tasks
+
     factory = get_session_factory()
     async with factory() as db:
         result = await db.execute(select(Tenant))
@@ -62,6 +62,6 @@ async def tasks_due_reminder(ctx: dict) -> None:
 
 
 # Register all job functions with the job registry
-from app.core.job_registry import register_job
+from app.core.job_registry import register_job  # noqa: E402
 
 register_job("tasks_due_reminder", tasks_due_reminder)