Enhance pricing table management in admin interface

- Added functionality to manage pricing tables, including creating, updating, and deleting pricing table entries.
- Integrated pricing table data fetching using React Query for improved state management and error handling.
- Updated the admin product management page to include a dialog for managing pricing tables, allowing users to input and display relevant pricing table information.
- Enhanced error handling for missing Stripe configuration and pricing table loading failures.

Author: PhiRho

frontend/next.config.ts

@@ -1,7 +1,9 @@
 import type { NextConfig } from "next";
 
 const nextConfig: NextConfig = {
-  /* config options here */
+  env: {
+    NEXT_PUBLIC_STRIPE_PUBLISHABLE_KEY: process.env.STRIPE_PUBLISHABLE_KEY,
+  },
 };
 
 export default nextConfig;