refactor(b3): dynamic entity registry, custom_fields permissions decoupled from contacts, write perms generated from registry

app/routes/custom_field_definitions.py

@@ -22,7 +22,7 @@ router = APIRouter(prefix="/api/v1/custom-fields", tags=["custom-fields-definiti
 @router.get(
     "/definitions",
     response_model=list[CustomFieldDefinitionResponse],
-    dependencies=[Depends(require_permission("contacts:read"))],
+    dependencies=[Depends(require_permission("custom_fields:read"))],
 )
 async def list_definitions(
     entity: str | None = Query(None, description="Filter by entity type (e.g. 'contact', 'company')"),
@@ -39,7 +39,7 @@ async def list_definitions(
     "/definitions",
     response_model=CustomFieldDefinitionResponse,
     status_code=201,
-    dependencies=[Depends(require_permission("contacts:write"))],
+    dependencies=[Depends(require_permission("custom_fields:write"))],
 )
 async def create_definition(
     body: CustomFieldDefinitionCreate,
@@ -58,7 +58,7 @@ async def create_definition(
 @router.patch(
     "/definitions/{definition_id}",
     response_model=CustomFieldDefinitionResponse,
-    dependencies=[Depends(require_permission("contacts:write"))],
+    dependencies=[Depends(require_permission("custom_fields:write"))],
 )
 async def update_definition(
     definition_id: str,
@@ -90,7 +90,7 @@ async def update_definition(
 @router.delete(
     "/definitions/{definition_id}",
     status_code=204,
-    dependencies=[Depends(require_permission("contacts:write"))],
+    dependencies=[Depends(require_permission("custom_fields:write"))],
 )
 async def delete_definition(
     definition_id: str,