fix(identity-wallet): address final code review feedback
- C1: Remove delete_item("managed-dids") from plc_monitor tests to fix
parallel execution; use DID-specific assertions instead of total count
in multi-identity tests (allows concurrent test registration)
- I1: Use imported formatCountdown() in AlertDetailScreen instead of
duplicating inline formatting logic
- I2: Remove AC references (AC6.1, AC6.2) from production code comments
- M1: Remove unused Urgency type import from AlertDetailScreen
- M2: Add explicit flexbox to .card-badge for badge stacking layout