WIP: the live queue serves the whole instance (#51)

[fiddur]

Draft to preserve WIP — not ready to merge. Pushed so this work survives a machine move; it still needs the steps in "What's left" below.

The bug it fixes (#51)

The file browser is its own diffity session, and every ref gets one. A reader asking a question on one session while the only agent sat parked (via diffity-live) on a different session left both waiting forever — the parked agent never saw the request, and the reader never got an answer.

What this does

Makes the live queue, its listeners, and the page's "listening" answer instance-wide instead of per-session: the request names its own thread, so whichever agent is parked anywhere on this instance takes it. Waiting and working counts stay per-session (they describe the requests a given page can see).

Touched: live.ts (claimNextLiveRequest() with no session filter; single listeners set; liveListenerTotal(); notifyLiveListeners() no-arg; waitForLiveRequest(waitMs, signal?) with abort-before-claim), review-routes.ts, server.ts (listening: liveListenerTotal() > 0), and the live-requests / idle-instance-guards tests.

State

• Implemented and green locally at the time of the commit (ce16513).
• Never reviewed. No review rounds have run on it.
• The branch is 5 commits behind develop — it was cut before fix: only dirt in a commented file blocks talking to the forge #77 (dirty-guard), feat: review bundles — a session's threads and tours as a portable file #80 (bundles), feat: diffity inbox — watch review-requested PRs and prepare them ahead #82 (inbox daemon) and feat: the inbox page — one click from a prepared review to a live diffity session #83 (inbox page) landed. feat: diffity inbox — watch review-requested PRs and prepare them ahead #82 in particular reworked live.ts/server.ts, so merge conflicts are expected there.

What's left before it can merge

1. Merge current develop into the branch (clean merge, no rebase) and resolve conflicts — most likely in live.ts and server.ts against feat: diffity inbox — watch review-requested PRs and prepare them ahead #82's live-queue changes.
2. Bump the patch version (npx tsx scripts/release.ts patch --no-git).
3. Run pnpm check / the full suite green.
4. Take it through the normal @code-reviewer round loop to 0 P1 / 0 P2.
5. Mark ready, squash-merge, deploy the global.

Local worktree while WIP: ~/nc/diffity-fork/live-queue.

Closes #51 (on merge).