Create NostrEmbed.vue component that renders nostr:note1, nostr:npub1, and nostr:nevent1 URIs as rich embedded cards. Add bech32 decoder utility with NIP-19 TLV support for nevent/nprofile. Extend useNostr with fetchNote() for single-note relay lookups. ChatMessage.vue now detects and strips nostr URIs, rendering them as inline embed cards. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>