GSoC 2025 Qualification Task: Migrate Subscription List Page to AG Grid and Update Site Menu

[maany]

The current Subscription page at /subscription/list uses the legacy streamed table concept.

In contrast, pages such as http://localhost:3000/did/list and http://localhost:3000/rse/list have been upgraded to use the new, high-performance AG Grid tables that efficiently load large datasets asynchronously.

Objectives

Migrate Subscription List

Replace the existing streamed table on the Subscription page with an AG Grid-based table.
Use existing AG Grid implementations (e.g., DID and RSE pages) as a reference for consistency and performance.

Enhance UX and Error Handling

Ensure smooth user interactions, including responsive design, loading indicators, and proper error messaging.
Optimize asynchronous data loading to improve performance.

Update Site Menu

Add "Subscriptions" to the header site menu to provide easy navigation to the Subscription page.
Testing and Documentation:

Write comprehensive tests to verify the functionality and reliability of the new implementation.

Acceptance Criteria:

• The Subscription page now uses an AG Grid-based table with asynchronous data loading.
• The table implementation matches the design and performance of other AG Grid-based pages.
  UX enhancements (e.g., loading states, error handling) are in place and tested.
• "Subscriptions" is added to the header menu, linking correctly to the Subscription page.
• All relevant tests pass and documentation is updated accordingly.