fix(settings): close cross-namespace, dispatch, and lifecycle races from second review

Confirmed and fixed, each with a regression test that failed first:

- Concurrent writes to different namespaces lost whole sections on disk
  (each persist rendered the full document from a stale text): the local
  provider serializes render->write->rename->text-commit on one internal
  persist chain shared by every namespace queue.
- One throwing settings/updated listener starved the rest (cordis emit
  stops at the first throw): commit fans out per listener via
  events.dispatch, contains individual failures, and rethrows the first
  INVARIANT-coded error only after every listener ran.
- Write queues ignored fiber/service lifecycle: the base init now
  registers a teardown that refuses new writes and drains queued chains;
  queued tasks re-verify service liveness and namespace ownership before
  running and again before committing, so a registrant disposed
  mid-flight is never notified and a disposed service never commits.
- Async watcher invocations could interleave (a slow stale call applied
  last): each watcher carries a serialized invocation chain — one call
  at a time, in commit order; JSDoc/doc pages state the async timing.
- update/replace borrowed the caller's object until the queued task ran:
  inputs are structured-clone snapshotted at call time; non-cloneable
  plain objects reject with a typed error.
- Composition guard now proves the documented fallback: the consumer
  uses the optional scoped-inject shape and boots both with the settings
  entry (hot publish) and without it (entry-config resolution, no scope).
- core-data-structures index: settings.md row added to the sub-page
  table in core.md/core.zh.md.

Both packages hold per-file 100% coverage across repeated runs.

docs/core-data-structures/core.zh.md

@@ -24,6 +24,7 @@ harness 是一个微内核：一个极小的核心加上众多插件。大多数
 | [commands.md](commands.md) | 人类命令 seam：定义、适配器发现、直接调用、结果与解析视图 |
 | [session.md](session.md) | 完整的 `SessionEventMap` 变体目录、`TurnTrigger`/`TurnEndReason`、`deriveMessages()`、执行封闭与独立事件 |
 | [persistence.md](persistence.md) | 持久性 seam：`SessionPersistence`、JSONL + SQLite 后端、`session/flush`、崩溃恢复、`SessionHeader` |
+| [settings.md](settings.md) | 用户设置 seam：`SettingsNamespace` 注册、分层解析（默认值 → 组合 `base` → 用户文档）、owner scope、热提交 |
 | [session-query.md](session-query.md) | 逻辑记录、有界精确事件读取、关系追踪、语义筛选器/文档与全文检索结果页 |
 | [session-title.md](session-title.md) | 持久标题快照、来源 provenance 与异步提供方契约 |
 | [system-prompt.md](system-prompt.md) | 逐次组装的上下文、工具提供方结果、提示词段落与协作式组装 |