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fix(signals): a landing's runs wait for its stale readers' re-derivation (#4217)

* fix(signals): a landing's runs wait for its stale readers' re-derivation (#4071)

A hold that lands while a render effect it held is a stale reader (its
mainline pass, served the committed value, stopped reading the flight)
published its held write at once; the reader's re-derivation on the
landed world ran a round later and could discover a new flight, leaving
the write on screen beside a frame that can only show its old value
(D-9, the A15 reveal corollary; fuzzer finding F2, U-5).

The landing still commits, but when `reruns` re-derives an effect, its
held runs are released by a callback queued last in this effect phase:
they become the first runs of the next round, the re-derivation's round.
If the re-derivation goes pending, that round parks and the runs park
with it, showing when the flight lands; otherwise they run ahead of the
re-derivation's own runs, in the same relative order as before. The
pre-landing re-derivation of the earlier prototype is not used, so the
#3404 frame-replacement order and the seeded projection refetch pins
stand.

+55 B minified on every scenario that ships the signals core.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_015hPxMkC3jg3Uivh65gvaf2

* perf(signals): offset the #4071 bytes in the core

Behavior-preserving size work in packages/signals/src/core, so the
landing fix ships without growing any scenario's minified size:

- `NewSet` (constants.ts): `Set` under a module binding. Rolldown marks
  a bare `new Set()` with a `/* @__PURE__ */` comment that survives
  minification (16 B a site); a construction through a binding carries
  none. Six core sites (async.ts x4, graph.ts, core.ts). Same constructor.
- `notifyEffectStatus` (effect.ts): no caller passes `status`/`error`;
  the parameters and the `blockStatus` plumbing they served in
  `notifyStatus`/`propagateS... (continued)

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