Added extensive debug logs to track:
- Input markdown preview and existing link count
- Each markdown link found with context and content
- Warnings when link URLs contain nostr URIs (should be protected)
- Detailed position information for each nostr URI match
- Whether matches are correctly identified as inside/outside link URLs
- Detection of nested markdown links in result (indicates bug)
This will help diagnose the timing issue where processing sometimes
works and sometimes doesn't.