Fixed 3 critical code quality issues:
1. Act() warnings in tests (9 tests):
- Wrapped all async state updates in act() blocks in usePhotoUpload.test.ts
- Tests using waitFor() now properly await state updates within act()
- All 21 tests pass with zero act() warnings
2. Missing toast cleanup on unmount:
- Added toastIdRef to track pending toast IDs
- Added cleanup useEffect that dismisses toasts on component unmount
- Prevents memory leaks and orphaned toast notifications
3. Dual error reporting channels (lines 23-28):
- Removed useEffect that synced hook error to local state AND called onError callback
- Now syncs hook error to local state only (for display)
- Parent components rely on hook error state, reducing dual-path confusion
- Toast error calls are explicit in catch block
Test Results:
- Frontend: 312/312 tests passing (includes 21 photo upload tests)
- Act() warnings: Eliminated
- No regressions introduced
