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/entity_links/routes.py

@@ -9,17 +9,21 @@ from sqlalchemy import select
 from sqlalchemy.ext.asyncio import AsyncSession
 
 from app.core.db import get_db
-from app.core.visibility import apply_visibility_filter
 from app.deps import get_current_user, require_permission
-from app.services.entity_permission_service import check_entity_access
 from app.plugins.builtins.entity_links.models import EntityLink
 from app.plugins.builtins.entity_links.schemas import EntityLinkRequest
+from app.services.entity_permission_service import check_entity_access
 
 router = APIRouter(prefix="/api/v1/entity-links", tags=["entity-links"])
 contact_router = APIRouter(prefix="/api/v1/contacts", tags=["entity-links"])
 company_router = APIRouter(prefix="/api/v1/companies", tags=["entity-links"])
 
-VALID_ENTITY_TYPES = {"contact", "company"}
+# Entity types validated dynamically against ENTITY_MODELS at runtime (P1-13 fix)
+
+def _is_valid_entity_type(entity_type: str) -> bool:
+    """Check if entity_type is registered in ENTITY_MODELS."""
+    from app.services.entity_permission_service import ENTITY_MODELS
+    return entity_type in ENTITY_MODELS
 
 
 def _parse_uuid(val: str, field: str) -> uuid.UUID:
@@ -44,7 +48,7 @@ async def link_file_to_entity(
     fid = _parse_uuid(file_id, "file_id")
     entity_id = _parse_uuid(body.entity_id, "entity_id")
 
-    if body.entity_type not in VALID_ENTITY_TYPES:
+    if not _is_valid_entity_type(body.entity_type):
         raise HTTPException(
             400, detail={"detail": "Invalid entity_type", "code": "invalid_entity_type"}
         )
@@ -103,7 +107,6 @@ async def unlink_file_from_entity(
 ):
     """Remove a link between a file and an entity."""
     tenant_id = uuid.UUID(current_user["tenant_id"])
-    user_id = uuid.UUID(current_user["user_id"])
     fid = _parse_uuid(file_id, "file_id")
     entity_id = _parse_uuid(body.entity_id, "entity_id")
 
@@ -131,7 +134,6 @@ async def list_file_links(
 ):
     """List all entities linked to a file."""
     tenant_id = uuid.UUID(current_user["tenant_id"])
-    user_id = uuid.UUID(current_user["user_id"])
     fid = _parse_uuid(file_id, "file_id")
 
     result = await db.execute(