Add exponential backoff / rate limiting to the "Retry" button

[Muskankr]

Currently "Retry" likely re-fires the request immediately and can be clicked repeatedly. Add basic backoff so repeated failures don't hammer the backend.

Acceptance criteria:

Retry button disabled briefly after each attempt, with increasing delay on repeated failures
Clear visual feedback while a retry is in progress
Resets to normal behavior after a successful load

[Ayush-0918]

I would like to work on this issue. Please assign to me.