Refactor billing schema for increased flexibility

The billing schema has been revamped to allow more flexible billing setups, supporting multiple line items per plan. Changes extend to related app and UI components for a seamless experience. As a result, the previously used 'line-items-mapper.ts' is no longer needed and has been removed.

apps/web/config/auth.config.ts

@@ -20,8 +20,8 @@ const authConfig = AuthConfigSchema.parse({
   // NB: Enable the providers below in the Supabase Console
   // in your production project
   providers: {
-    password: true,
-    magicLink: false,
+    password: process.env.NEXT_PUBLIC_AUTH_PASSWORD === 'true',
+    magicLink: process.env.NEXT_PUBLIC_AUTH_MAGIC_LINK === 'true',
     oAuth: ['google'],
   },
 } satisfies z.infer<typeof AuthConfigSchema>);