feat(demo): P3.5 inbox sidebar + inbox smoke (P3 complete)

message-demo gains a per-person Inbox rail (useInbox, done/snooze); sending
surfaces a NEEDS_REPLY item in the other pane; reading auto-resolves it.
smoke-inbox.mjs proves the event-driven flow end-to-end (send -> relay ->
projector -> inbox -> read -> DONE). Realtime smoke still passes.

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

pnpm-lock.yaml

@@ -20,6 +20,9 @@ importers:
 
   apps/message-demo:
     dependencies:
+      '@insignia/iios-inbox-web':
+        specifier: workspace:*
+        version: link:../../packages/iios-inbox-web
       '@insignia/iios-kernel-client':
         specifier: workspace:*
         version: link:../../packages/iios-kernel-client