Replace local-only draft storage with the new `app.bsky.draft.*` server API:
- getDrafts, createDraft, updateDraft, deleteDraft endpoints
Key changes:
- Add api.ts with type converters (ComposerState <-> server Draft)
- Update hooks.ts to use server API instead of local storage
- Simplify storage.ts/storage.web.ts for local media caching only
- Media stored locally via localRef pattern (filepath in server draft)
- GIFs stored as external embeds with Tenor URL + dimensions
- Hide drafts button when replying (reply drafts not supported)
- Show "different device" note when media is missing locally
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
Samuel Newman
666e1318b2