Fixes#1368
Previously, was duplicated in 4 places with 3 subtly different fallback behaviors:
1. inline-citation.tsx: returned on error
2. markdown-text.tsx: returned on error
3. assistant-message.tsx: returned on error
4. citation.tsx: returned on error
Created canonical in that:
- Returns
- Strips prefix from hostname
- Returns on invalid URL (safest contract)
Updated all 4 call sites:
- inline-citation.tsx: (preserves original fallback)
- markdown-text.tsx: (preserves original fallback)
- assistant-message.tsx: (drop-in, both return )
- citation.tsx: (drop-in, both return )
Co-authored-by: guangyang1206 <guangyang1206@users.noreply.github.com>
