Fix cart load_service_components: use os.path instead of Path

Avoid UnboundLocalError with Path by using os.path directly.

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

cart/app.py

@@ -140,8 +140,8 @@ def create_app() -> "Quart":
     app.jinja_env.globals["cart_quantity_url"] = lambda product_id: f"/quantity/{product_id}/"
     app.jinja_env.globals["cart_delete_url"] = lambda product_id: f"/delete/{product_id}/"
 
-    from pathlib import Path
-    load_service_components(str(Path(__file__).resolve().parent), service_name="cart")
+    import os as _os
+    load_service_components(_os.path.dirname(_os.path.abspath(__file__)), service_name="cart")
 
     from shared.sx.handlers import auto_mount_fragment_handlers
     auto_mount_fragment_handlers(app, "cart")