Feat v0.5.2 chat surface

Chat surface package (packages/chat/) with conversation list, message
thread, compose bar, participant sidebar, create conversation dialog,
typing indicators, read receipts, message editing, and message deletion.
Built on chat-core library with realtime event subscriptions.

Fix stale token login deadlock: REST client auth endpoints excluded
from 401 retry loop, 8s defensive boot timeout on auth.boot().

Fix bundled package permissions: auto-grant with NULL granted_by and
set status active on install.

Switch docker-compose to named volume for remote Docker host compat.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

VERSION

@@ -1 +1 @@
-0.5.1
+0.5.2