1. Root cause: cmd/msrc/generate.go
Problem: The MSRC feed generator panicked when the January 2026 feed
wasn't available. The grace period was only 5 days, but MSRC feed
publication dates vary (not available right now).
Fix: Extended grace period from 5 to 15 days.
2. Defensive fix:
server/vulnerabilities/macoffice/integration_sync_test.go
Problem: Test only checked for files from the last 2 days, which failed
when the NVD repo hadn't published for a few days.
Fix: Extended tolerance to 7 days.
