refactor: enforce strict architecture rules and add Pydantic response models

- Update architecture rules to be stricter (API-003 now blocks ALL exception
  raising in endpoints, not just HTTPException)
- Update get_current_vendor_api dependency to guarantee token_vendor_id presence
- Remove redundant _get_vendor_from_token helpers from all vendor API files
- Move vendor access validation to service layer methods
- Add Pydantic response models for media, notification, and payment endpoints
- Add get_active_vendor_by_code service method for public vendor lookup
- Add get_import_job_for_vendor service method with vendor validation
- Update validation script to detect exception raising patterns in endpoints

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

app/api/v1/vendor/profile.py

@@ -2,7 +2,8 @@
 """
 Vendor profile management endpoints.
 
-Vendor Context: Uses token_vendor_id from JWT token (authenticated vendor API pattern)
+Vendor Context: Uses token_vendor_id from JWT token (authenticated vendor API pattern).
+The get_current_vendor_api dependency guarantees token_vendor_id is present.
 """
 
 import logging
@@ -12,7 +13,6 @@ from sqlalchemy.orm import Session
 
 from app.api.deps import get_current_vendor_api
 from app.core.database import get_db
-from app.exceptions import InsufficientPermissionsException, InvalidTokenException
 from app.services.vendor_service import vendor_service
 from models.database.user import User
 from models.schema.vendor import VendorResponse, VendorUpdate
@@ -21,20 +21,13 @@ router = APIRouter(prefix="/profile")
 logger = logging.getLogger(__name__)
 
 
-def _get_vendor_from_token(current_user: User, db: Session):
-    """Helper to get vendor from JWT token."""
-    if not hasattr(current_user, "token_vendor_id"):
-        raise InvalidTokenException("Token missing vendor information. Please login again.")
-    return vendor_service.get_vendor_by_id(db, current_user.token_vendor_id)
-
-
 @router.get("", response_model=VendorResponse)
 def get_vendor_profile(
     current_user: User = Depends(get_current_vendor_api),
     db: Session = Depends(get_db),
 ):
     """Get current vendor profile information."""
-    vendor = _get_vendor_from_token(current_user, db)
+    vendor = vendor_service.get_vendor_by_id(db, current_user.token_vendor_id)
     return vendor
 
 
@@ -45,10 +38,7 @@ def update_vendor_profile(
     db: Session = Depends(get_db),
 ):
     """Update vendor profile information."""
-    vendor = _get_vendor_from_token(current_user, db)
-
-    # Verify user has permission to update vendor
-    if not vendor_service.can_update_vendor(vendor, current_user):
-        raise InsufficientPermissionsException(required_permission="vendor:profile:update")
-
-    return vendor_service.update_vendor(db, vendor.id, vendor_update)
+    # Service handles permission checking and raises InsufficientPermissionsException if needed
+    return vendor_service.update_vendor(
+        db, current_user.token_vendor_id, vendor_update, current_user
+    )