Keep a late-arriving server-component boundary claimable and its slot range live - #2967

Follow-up to #2964. With a 2s delay added to noteView in the notes example, /notes/0 renders correctly and then the app stops responding: clicking another note changes the URL and fetches nothing, and New/Edit/home change the URL and nothing else. Two independent causes, both in the frames client.

1. _$HY.done is no longer "the page is complete"

Once post-done swaps became held-until-claimed, a fragment settling after global hydration keeps its placeholder, fallback and template in place until its boundary registers as claimant — and the replay that follows is what delivers the boundary element. documentStreaming() read done as "never", so a boundary rendering in that window (a frames slot fill, or a lazy route module running after the root pass) mounted a fresh frame and orphaned the markup the replay then delivered. Captured from a live run:

documentBoundary 279061e8-0-noteView {claimed: false, found: false, streaming: false}
fresh frame      279061e8-0-noteView
fe               sc-84ece717-0-appView-children-0     ← the swap, afterwards

The region is visible but owned by nothing, and because the id is never claimed, intercept answers every later call for that function with the document placeholder instead of fetching — dynamic's equals-gate then makes each navigation a no-op.

boundaryMayArrive() replaces documentStreaming(): still streaming, or an unresolved pl-* placeholder is in the page. So a waiter cannot strand a region forever, a reveal that exhausts the page's deferred fragments releases waiters to mount fresh.

2. The claim scope severed the slot range's reactivity

A slot fill claims under the producer's hydration keys, and claiming runs through runWithOwner — which clears tracking along with the owner. With the claim inside insert's accessor, the binding's first read happened in that untracked window, so it stayed reactive only by accident: when the read returned another accessor, insert re-read it and picked up the dependency. A <Loading> answering a still-pending streamed fragment returns its fallback nodes instead, so the effect ended up with no dependency at all and the range went permanently inert. The boundary's own resume still claimed the swapped-in server markup — the region looks right — but nothing downstream ever re-rendered it. Instrumented: the slot accessor ran once, at claim time, and never again; a route change out of the note produced zero further evaluations.

The claim now wraps the insert call. The first evaluation is the render effect's own synchronous compute — still under the producer's keys, but tracked.

Tests

• frames-late-boundary-client: a held fragment still owes its element after done (asserting the follow-up call actually reaches the network — the user-visible symptom), plus the give-up path when no deferred fragment remains.
• test/hydration/adopted-slot-live.spec.tsx: the live slot range. It lives in the hydrate config because claimRender bails out entirely without sharedConfig.getNextContextId, so the untracked window never opens in the plain client config — hence the one alias line added to vite.config.hydrate.mjs.

All three fail on the prior code. Suites green: 340 client, 77 hydrate, 201 server.

Verified end to end in the notes example (dev and a production build, fresh origins, real clicks): /notes/0 → other notes each fetch and morph, and New/Edit/home all navigate and render.

🤖 Generated with Claude Code