Merge remote-tracking branch 'origin/master' into xtr/react-loop-simplification

# Conflicts:
#	docs/cordis-catalog/services.md
#	docs/core-data-structures/session.i18n.yaml
#	docs/persistence-catalog.md
#	packages/cordis/tool-cordis/src/api-catalog.ts

docs/core-data-structures/session.i18n.yaml

@@ -2,5 +2,5 @@
 # side as of the last confirmed-consistent state. Both languages carry equal authority;
 # after editing either side, bring the other along and re-record with:
 #   pnpm run verify-translation-pairing --write docs/core-data-structures/session.md
-session.md: 85eebf81e07774e4d9095cfbf042330a90d30a9e
-session.zh.md: 356a283c4ebe041c3690ae2e3a23ff1be7b4722f
+session.md: b7acd54067068495c474a0617f057a295b8b287b
+session.zh.md: 7b6984f27ec6b391afc64b7967c5ba59e4a53da7

docs/core-data-structures/session.md

@@ -93,6 +93,29 @@ interface SessionEventMap {
    * It is log-only; the latest snapshot reconstructs the request header.
    */
   'request/header': { header: EpochHeader; reason: RequestHeaderReason }
+  /**
+   * Marks the end of a constructor seed. Events before it have smaller seq
+   * values and came from the seed (resume, fork, or replay); this lifecycle
+   * produced none of them. This log-only event is the durable projection of
+   * {@link Session.firstLiveSeq}. Its payload is empty — position and `time`
+   * carry the meaning.
+   *
+   * Locate the LAST one in stored history. A seed already ending in one is not
+   * re-marked, so reopening an untouched session does not grow its log per
+   * pickup and the event need not be at the current `firstLiveSeq`.
+   *
+   * `Session`'s constructor is the only legitimate writer. The invariant
+   * companion deliberately constrains nothing here, so a plugin appending one
+   * would silently classify every live bracket before it as seed history.
+   *
+   * An owner of a standalone open/close bracket (`compact/start` …
+   * `compact/end`) reads it because seed history and live work are otherwise
+   * byte-identical: an unmatched opening marker before this event belongs to
+   * an ended lifecycle, whatever ended it. NOT a liveness signal about other
+   * writers — a concurrently live session holds its own boundary elsewhere,
+   * so tolerating concurrent writers needs a signal beyond the log.
+   */
+  'session/end-seed': Record<string, never>
 }
 ```
 
@@ -322,14 +345,25 @@ declare class Session {
   get id(): SessionId;
   /**
    * The first seq appended IN THIS PROCESS: the length of the constructor
-   * seed (0 without one). Events below it entered through construction —
-   * replay, fork, or resume — and were never published on the `session/event`
-   * firehose (constructor seeds do not emit), so consumers that replay the
-   * log as a publication substitute (telemetry adoption) start here. Distinct
-   * from `header.seedLength`, the DURABLE fork-lineage boundary: a resumed
-   * session's constructor seed is its full stored log, while its header keeps
-   * the original fork value — this field is the in-process construction fact
-   * and is deliberately not persisted.
+   * seed (0 without one). Events with smaller seq values entered through
+   * construction — replay, fork, or resume — and were never published on the
+   * `session/event` firehose (constructor seeds do not emit), so consumers
+   * that replay the log as a publication substitute (telemetry adoption)
+   * start here. Distinct from `header.seedLength`, the DURABLE fork-lineage
+   * boundary: a resumed session's constructor seed is its full stored log,
+   * while its header keeps the original fork value — this field is the
+   * in-process construction fact.
+   *
+   * Not persisted itself: a seeded session projects it into the log as the
+   * `session/end-seed` event, which is what a consumer reading STORED history
+   * reads. Locate the LAST such event, not necessarily one at this seq — a
+   * seed already ending in one is not re-marked, so reopening an untouched
+   * session leaves that event at a smaller seq than `firstLiveSeq`. Prefer
+   * this field in-process: it is exact before the marker reaches storage.
+   *
+   * When this lifecycle appends the marker, it occupies this seq before the
+   * store attaches and therefore does not publish either. Otherwise this seq
+   * holds an ordinary published write.
    */
   readonly firstLiveSeq: number;
   constructor(id: SessionId, seed?: readonly SessionEvent[], header?: SessionHeader);
@@ -480,6 +514,16 @@ A turn encloses one model-loop execution, not the whole session log. Idle inject
 
 The optional `dsh-session/invariant` companion enforces the relations owned by core: turn and step numbering, execution-event enclosure, and same-step tool call/result pairing. Merge-extensible event relations belong to the plugin that declares them, so core does not reject an unknown event merely because no turn is open. See [the standalone-event decision](../../.agents/notes/implemented/simplification/2026-07-28-remove-synthetic-log-only-turns.md).
 
+## The end-seed boundary: `session/end-seed`
+
+A seeded session — resume, fork, or replay — appends this log-only event immediately after its constructor seed, as its first live write. Events before it have smaller seq values and came from the seed. It is the durable projection of `firstLiveSeq`: that field answers where this lifecycle's writes start for a consumer holding the object, while the event answers the same question for one holding only stored bytes. The payload is empty, so position and `time` carry the whole meaning, and it produces no message. `Session`'s constructor is the only legitimate writer.
+
+An empty seed writes nothing, and a seed already ending in `session/end-seed` is not re-marked, so reopening an untouched session does not grow its log per pickup. Locate the LAST `session/end-seed` in stored history rather than assuming one exists at `firstLiveSeq`: after a pickup with no work, the event has a smaller seq than the next lifecycle's `firstLiveSeq`.
+
+It exists because seed history and live work are otherwise byte-identical, which defeats any plugin owning a standalone open/close bracket: an unmatched `compact/start` reads the same whether the writer crashed mid-compaction or is compacting right now. An opening marker before `session/end-seed` came from the constructor seed and belongs to an ended lifecycle, whatever ended it (a crash, a succeeding process, or a fork out of a still-running parent), so its owner may treat it as dead. That covers only brackets *this* session inherited: a concurrently live session holding an open bracket over the same history has its own boundary elsewhere, so tolerating concurrent writers needs a liveness signal beyond the log. Core writes the boundary and reads nothing from it — a bracket's vocabulary stays with its owning plugin, which is why crash repair closes turn/step/tool boundaries and never `compact/*`.
+
+Activity ordering excludes the boundary through `lastActivityTime(events)`: picking a session up is not work, and lazy resume means browsing writes one, so a resume picker or session list ordering by log tail would float every opened session to the top.
+
 ## Plugin-contributed log-only events
 
 A plugin may declaration-merge extra `SessionEventMap` types. These are **log-only**: NOT `SurfaceEventType`s (they carry no `surfaceOp` and contribute nothing to derived history). Their owner decides whether they belong to an open execution turn or may stand between turns, and enforces any relation in its own invariant companion. The full per-event enumeration — core and plugin-contributed alike, with payloads and provenance — is the generated [persistence log event catalog](../persistence-catalog.md); the compaction seam's `compact/*` semantics are discussed on [compaction.md](compaction.md).

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

@@ -93,6 +93,29 @@ interface SessionEventMap {
    * It is log-only; the latest snapshot reconstructs the request header.
    */
   'request/header': { header: EpochHeader; reason: RequestHeaderReason }
+  /**
+   * Marks the end of a constructor seed. Events before it have smaller seq
+   * values and came from the seed (resume, fork, or replay); this lifecycle
+   * produced none of them. This log-only event is the durable projection of
+   * {@link Session.firstLiveSeq}. Its payload is empty — position and `time`
+   * carry the meaning.
+   *
+   * Locate the LAST one in stored history. A seed already ending in one is not
+   * re-marked, so reopening an untouched session does not grow its log per
+   * pickup and the event need not be at the current `firstLiveSeq`.
+   *
+   * `Session`'s constructor is the only legitimate writer. The invariant
+   * companion deliberately constrains nothing here, so a plugin appending one
+   * would silently classify every live bracket before it as seed history.
+   *
+   * An owner of a standalone open/close bracket (`compact/start` …
+   * `compact/end`) reads it because seed history and live work are otherwise
+   * byte-identical: an unmatched opening marker before this event belongs to
+   * an ended lifecycle, whatever ended it. NOT a liveness signal about other
+   * writers — a concurrently live session holds its own boundary elsewhere,
+   * so tolerating concurrent writers needs a signal beyond the log.
+   */
+  'session/end-seed': Record<string, never>
 }
 ```
 
@@ -324,14 +347,25 @@ declare class Session {
   get id(): SessionId;
   /**
    * The first seq appended IN THIS PROCESS: the length of the constructor
-   * seed (0 without one). Events below it entered through construction —
-   * replay, fork, or resume — and were never published on the `session/event`
-   * firehose (constructor seeds do not emit), so consumers that replay the
-   * log as a publication substitute (telemetry adoption) start here. Distinct
-   * from `header.seedLength`, the DURABLE fork-lineage boundary: a resumed
-   * session's constructor seed is its full stored log, while its header keeps
-   * the original fork value — this field is the in-process construction fact
-   * and is deliberately not persisted.
+   * seed (0 without one). Events with smaller seq values entered through
+   * construction — replay, fork, or resume — and were never published on the
+   * `session/event` firehose (constructor seeds do not emit), so consumers
+   * that replay the log as a publication substitute (telemetry adoption)
+   * start here. Distinct from `header.seedLength`, the DURABLE fork-lineage
+   * boundary: a resumed session's constructor seed is its full stored log,
+   * while its header keeps the original fork value — this field is the
+   * in-process construction fact.
+   *
+   * Not persisted itself: a seeded session projects it into the log as the
+   * `session/end-seed` event, which is what a consumer reading STORED history
+   * reads. Locate the LAST such event, not necessarily one at this seq — a
+   * seed already ending in one is not re-marked, so reopening an untouched
+   * session leaves that event at a smaller seq than `firstLiveSeq`. Prefer
+   * this field in-process: it is exact before the marker reaches storage.
+   *
+   * When this lifecycle appends the marker, it occupies this seq before the
+   * store attaches and therefore does not publish either. Otherwise this seq
+   * holds an ordinary published write.
    */
   readonly firstLiveSeq: number;
   constructor(id: SessionId, seed?: readonly SessionEvent[], header?: SessionHeader);
@@ -484,6 +518,16 @@ interface TurnEndReasonMap {
 
 可选的 `dsh-session/invariant` 配套插件会强制核心拥有的关系：轮次与步骤编号、执行事件封闭，以及同一步骤内的工具调用／结果配对。可合并扩展事件的关系由声明它的插件拥有，因此核心不会仅因没有开放轮次就拒绝未知事件。见[独立事件决策](../../.agents/notes/implemented/simplification/2026-07-28-remove-synthetic-log-only-turns.md)。
 
+## 种子结束边界：`session/end-seed`
+
+带种子的会话（恢复、fork 或回放）紧接构造种子之后追加这个仅日志事件，作为自己的第一次实时写入。在它之前的事件具有更小的 seq，且来自种子。它是 `firstLiveSeq` 的持久投影：该字段为持有对象的消费方回答本生命周期的写入从哪里开始，该事件则为只持有存储字节的消费方回答同一问题。payload 为空，因此位置与 `time` 承载全部含义，且不产生任何消息。`Session` 的构造函数是唯一合法的写入方。
+
+空种子不写入任何内容；种子本身已以 `session/end-seed` 结尾时不会重复标记，因此重新打开一个未被改动的会话不会每次拾起都增长日志。应定位存储历史中的最后一条 `session/end-seed`，而不是假定 `firstLiveSeq` 处一定有一条：在一次没有产生工作的拾起之后，该事件的 seq 会小于下一个生命周期的 `firstLiveSeq`。
+
+它之所以必要，是因为种子历史与实时工作在字节层面完全相同，这会让任何拥有独立开／闭括号的插件失效：一个未配对的 `compact/start`，无论写入方是在压缩中途崩溃、还是此刻正在压缩，读起来都一样。在 `session/end-seed` 之前的开启标记来自构造种子，并且属于一个已结束的生命周期，无论结束原因为何（崩溃、进程接替，或从仍在运行的父会话 fork 出来），因此其所有方可以视之为已死。这只覆盖*本*会话继承的括号：另一个并发存活的会话可能在同一段历史上持有开放括号，而它自己的边界在别处，因此容忍并发写入方还需要日志之外的存活信号。核心写入该边界但不从中读取任何内容——括号的词汇表仍归其所属插件，这也正是崩溃修复只关闭轮次／步骤／工具边界而从不处理 `compact/*` 的原因。
+
+活动排序通过 `lastActivityTime(events)` 排除该边界：接手会话不算工作，而惰性恢复意味着浏览就会写入一个，因此按日志尾部排序的恢复选择器或会话列表会把每个打开过的会话顶到最前。
+
 ## 插件贡献的仅日志事件
 
 插件可以通过 declaration merging 添加额外的 `SessionEventMap` 类型。这些是**仅日志**事件：不是 `SurfaceEventType`（不携带 `surfaceOp`，不参与派生历史）。事件所有方决定它们属于一个开放的执行轮次，还是可以独立位于轮次之间，并在自己的不变量配套插件中强制所需关系。完整的逐事件枚举（核心与插件贡献的，含 payload 与溯源信息）见生成的[持久化日志事件目录](../persistence-catalog.md)；压缩 seam 的 `compact/*` 语义在 [compaction.md](compaction.md) 中讨论。