Fifth library variant that keeps folder sync for offline/local use
AND adds Nostr relay sync for cross-device reach via WebSocket.
Both transports run simultaneously - writes go to folder AND Nostr,
sync imports from both and bridges events between them.
Works from file:// since Nostr uses WebSocket (not fetch/WebRTC).
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
