iOS: thread link chip shows "Thread no longer available" for a thread in a project created moments earlier #30111

A t3-thread://v2/<environmentId>/<threadId> link in an assistant message renders as "Thread no longer available"
in the iOS app when the linked thread was created about half a second after its project. The thread exists and is
active. The desktop app renders the same message with the thread's title and project icon.

Steps:

1. Over MCP, create a project (t3_project_create), then start a thread in it right away (t3_thread_launch).
2. Within a few seconds, post an assistant message in another thread that contains the new thread's link.
3. Open that thread on iOS.

Expected: the chip shows the thread title and opens the thread.
Actual: the chip reads "Thread no longer available". Desktop on the same server resolves it.

Seen twice on 2026-11-02 (desktop 0.1.6, server on the Mac, iOS app paired to it). Links to threads in projects
that already existed resolved on the same phone in the same session.

Desktop builds resolve the chip from the shell store with useThreadShell and fall back to the "no longer
available" label without a server lookup. If iOS does the same, a fallback read by thread id on a miss (or
re-resolving when the shell store later gains the thread) would fix it.