Warn customs users when accepting an expired guarantee
requested to merge KKsurendran06/etir-national-application:fix/guarantee-expiration-warning into dev-1.0.3
closes #275
What changed
- Added a red warning on the Accept Guarantee screen when the guarantee validity date has passed.
- The guarantee remains valid through its stated validity date.
- The warning does not prevent the customs user from accepting the guarantee.
Testing
- Added tests for expired, current-day, future, and missing validity dates.
- Confirmed the Accept button remains enabled.
- Component tests: 3 passed.
- Frontend lint and production build passed.
- Manually verified in EU union mode.
Screenshot: 
Edited by KK Surendran