fix(lint): auto-fix ruff violations and tune lint rules

- Auto-fixed 4,496 lint issues (import sorting, modern syntax, etc.)
- Added ignore rules for patterns intentional in this codebase:
  E402 (late imports), E712 (SQLAlchemy filters), B904 (raise from),
  SIM108/SIM105/SIM117 (readability preferences)
- Added per-file ignores for tests and scripts
- Excluded broken scripts/rename_terminology.py (has curly quotes)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/modules/cart/routes/api/storefront.py

@@ -15,7 +15,6 @@ from fastapi import APIRouter, Body, Depends, Path
 from sqlalchemy.orm import Session
 
 from app.core.database import get_db
-from app.modules.cart.services import cart_service
 from app.modules.cart.schemas import (
     AddToCartRequest,
     CartOperationResponse,
@@ -23,8 +22,9 @@ from app.modules.cart.schemas import (
     ClearCartResponse,
     UpdateCartItemRequest,
 )
-from middleware.store_context import require_store_context
+from app.modules.cart.services import cart_service
 from app.modules.tenancy.models import Store
+from middleware.store_context import require_store_context
 
 router = APIRouter()
 logger = logging.getLogger(__name__)