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/models/entity_attachment.py

@@ -5,7 +5,7 @@ from __future__ import annotations
 import uuid
 from datetime import datetime
 
-from sqlalchemy import DateTime, ForeignKey, Index, String
+from sqlalchemy import DateTime, ForeignKey, Index, String, text
 from sqlalchemy.dialects.postgresql import UUID as PGUUID
 from sqlalchemy.orm import Mapped, mapped_column
 
@@ -15,7 +15,7 @@ from app.models.owned_mixin import OwnedMixin
 
 class EntityAttachment(Base, TenantMixin, OwnedMixin):
     """Links a DMS file to any entity (contact, address, invoice, etc.).
-    
+
     The actual file is stored in the DMS (files table).
     This table only holds the reference + category + display_name.
     """
@@ -42,10 +42,10 @@ class EntityAttachment(Base, TenantMixin, OwnedMixin):
         PGUUID(as_uuid=True), ForeignKey("users.id", ondelete="SET NULL"), nullable=True
     )
     created_at: Mapped[datetime] = mapped_column(
-        DateTime(timezone=True), nullable=False, server_default=__import__('sqlalchemy').func.now()
+        DateTime(timezone=True), nullable=False, server_default=text('now()')
     )
     updated_at: Mapped[datetime] = mapped_column(
-        DateTime(timezone=True), nullable=False, server_default=__import__('sqlalchemy').func.now(),
-        onupdate=__import__('sqlalchemy').func.now(),
+        DateTime(timezone=True), nullable=False, server_default=text('now()'),
+        onupdate=text('now()'),
     )
     deleted_at: Mapped[datetime | None] = mapped_column(DateTime(timezone=True), nullable=True)