feat(gen2-migration): add test script to product-catalog app

[sanjanaravikumar-az]

This script provides frontend-backend testing for the product-catalog app's Amplify backend.

What it tests:

• GraphQL queries (listProducts, getProduct, listUsers, getUser, listComments, commentsByProductId, checkLowStock Lambda)
• GraphQL mutations (CRUD operations for Products, Users, and Comments)
• S3 storage operations (upload product images, get signed URLs)
• Role-Based Access Control (ADMIN, MANAGER, VIEWER permissions)
• Business logic (product filtering, sorting, low stock report generation)

How it works:

• Authenticates via Cognito user pool (IAM auth required for all operations)
• Runs query tests to verify data retrieval
• Performs full CRUD cycle on Products, Users, and Comments (create → update → delete)
• Tests S3 storage by uploading images and retrieving signed URLs
• Tests full product-with-image workflow (create product → upload image → link image to product)
• Validates role-based permissions based on current user's role
• Tests client-side filtering and sorting logic
• Cleans up test data and signs out

Users need to update TEST_USER credentials before running tests.

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[9pace]

Seems like gen2-test-script.ts still has residual duplicated code from the original PR.

[9pace]

We should import from test-utils following the same pattern as in gen1 script