eleven / ocho Public

Multi-thread + DMs: threads, user keypairs, and the full message toolkit (#17)

Turns each lchat instance from one shared group chat into a multi-thread workspace:
DMs and groups are one primitive (a thread with N members), the instance is the
trust boundary (open roster + admin), and every thread has its own AES key wrapped
to each member's keypair (ECIES). The server still only ever sees opaque ciphertext
plus key blobs it can't open.

- User keypairs (ECDH P-256); per-thread keys wrapped per-member; instance key for
  all-members content (profile photos), server-blind.
- Master-detail UI (desktop) + stacked mobile nav; new-chat / new-group, members,
  add-people, leave, edit-group, edit-profile.
- Message toolkit: reactions, edits (15-min window), replies, typing indicators,
  time separators + hover times, link previews, attachments, avatars; desktop
  hover react/reply/edit affordances.
- Per-thread push (SW decrypts with the thread key); admin console is roster-only
  (no group key); script-post API + tool re-keyed to the keypair model.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>