- Fix getNpubFallbackDisplay to return names without @ prefix
- Update all call sites to consistently add @ when rendering mentions
- Fix incomplete error handling in getNpubFallbackDisplay catch block
- Add nprofile support to addLoadingClassToProfileLinks
- Extract shared isProfileInCacheOrStore utility to eliminate duplicate loading state checks
- Update ResolvedMention and NostrMentionLink to use shared utility
This ensures consistent @ prefix handling across all profile display contexts
and eliminates code duplication for profile loading state detection.