fix(goal-session): discriminate plugin turn triggers

.agents/notes/implemented/feature/2026-07-21-log-backed-session-titles.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
-2026-07-21-log-backed-session-titles.md: 0ab8f5b42004892c3ca6d6598cfacd57fbc9300c
-2026-07-21-log-backed-session-titles.zh.md: 7dfbc5cc378b8cf16743fceb594d8bcb47477637
+2026-07-21-log-backed-session-titles.md: d322b58c32d44c07d8d18618546225e7001ab025
+2026-07-21-log-backed-session-titles.zh.md: cb70533d52310574c56c7b0177b9b1ba34d7176a

.agents/notes/implemented/feature/2026-07-21-log-backed-session-titles.md

@@ -18,7 +18,7 @@ The [`session-title` capability family](../../../../packages/session-title/READM
 
 Every accepted revision is a log-only `session/title` event. Its payload contains normalized non-empty text, the exact eligible human `user/message` seqs used to derive it, and either fallback provenance or the registered provider id plus optional provider/model route. Before an auxiliary title-model dispatch, the shared helper appends a log-only `session/title-llm-request` event containing the title-provider id, exact source seqs, route, system prompt, messages, and output-token cap; a later generation failure leaves the request auditable. The dispatched envelope is deep-frozen to preserve exact agreement with that record but carries no process-local agent-loop request identity, so loop-only reconstruction checks do not compare it with the main conversation header. Validation failures that never reach dispatch create no request event. `foldSessionTitle()` selects the latest title event and adds that event's seq and timestamp as `SessionTitleSnapshot`. Neither event enters `session.surface` or `deriveMessages()`.
 
-The core session package exposes `ctx.sessions.appendOutOfBand()` only for plugin event types whose owners also declaration-merge an `OutOfBandSessionEventMap` marker. An open turn receives the log-only event directly and owns its normal checkpoint. A closed log receives `turn/start → event → turn/end` under the plugin's trigger, followed by an awaited flush. Once the synthetic turn opens, target-append failure still attempts to close and flush it; detach is deferred until the sequence settles. Session titles contribute the `session-title` zero-step trigger and opt both title event types into this seam.
+The core session package exposes `ctx.sessions.appendOutOfBand()` only for plugin event types whose owners also declaration-merge an `OutOfBandSessionEventMap` marker. An open turn receives the log-only event directly and owns its normal checkpoint. A closed log receives `turn/start → event → turn/end` under the plugin's trigger, followed by an awaited flush. Once the synthetic turn opens, target-append failure still attempts to close and flush it; detach is deferred until the sequence settles. Session titles contribute the source-free `session-title` zero-step trigger and opt both title event types into this seam. No message caused that trigger, so consumers of the merge-extensible `TurnTriggerMap` discriminate `kind` before reading variant fields; goal-round admission, for example, ignores every non-`message` trigger.
 
 ### Input and asynchronous timing
 

.agents/notes/implemented/feature/2026-07-21-log-backed-session-titles.zh.md

@@ -18,7 +18,7 @@ Status: implemented
 
 每个已接受的修订都是纯日志 `session/title` 事件。其载荷包含规范化后的非空文本、用于派生标题的所有合格且来源为人类的 `user/message` 的准确 seq，以及回退来源信息，或已注册的提供方 id 加可选的提供方和模型路由。辅助标题模型发起调用前，共享辅助组件会追加一个纯日志 `session/title-llm-request` 事件，其载荷包含标题提供方 id、准确的源 seq、路由、系统提示词、消息和输出 token 上限；即使后续生成失败，这次请求仍可审计。发送的请求信封经过深度冻结，以确保其与该记录精确一致，但它有意不携带进程本地的 agent loop（智能体循环）请求身份，因此仅针对 agent loop 的重建检查不会将它与主对话请求头进行比较。未进入调用阶段的验证失败不会创建请求事件。`foldSessionTitle()` 选择最新的标题事件，并将该事件的 seq 和时间戳加入 `SessionTitleSnapshot`。这两类事件都不会进入 `session.surface` 或 `deriveMessages()`。
 
-核心会话包通过 `ctx.sessions.appendOutOfBand()` 暴露这一接口，但只允许所属插件同时通过声明合并向 `OutOfBandSessionEventMap` 添加标记的插件事件类型使用。开放轮次会直接接收纯日志事件，并负责其常规检查点。已关闭的日志会在该插件的触发器下接收 `turn/start → event → turn/end`，随后等待刷写完成。合成轮次一旦开启，即使目标追加失败，系统仍会尝试将其关闭并刷写；整个序列完成前会延迟 detach。会话标题提供 `session-title` 零步骤触发器，并让这两类标题事件都使用这一服务边界。
+核心会话包通过 `ctx.sessions.appendOutOfBand()` 暴露这一接口，但只允许所属插件同时通过声明合并向 `OutOfBandSessionEventMap` 添加标记的插件事件类型使用。开放轮次会直接接收纯日志事件，并负责其常规检查点。已关闭的日志会在该插件的触发器下接收 `turn/start → event → turn/end`，随后等待刷写完成。合成轮次一旦开启，即使目标追加失败，系统仍会尝试将其关闭并刷写；整个序列完成前会延迟 detach。会话标题提供不带消息来源的 `session-title` 零步骤触发器，并让这两类标题事件都使用这一服务边界。该触发器并非由消息引起，因此可合并扩展的 `TurnTriggerMap` 的消费方在读取变体字段前，会先根据 `kind` 判别类型；例如，目标轮次准入会忽略所有非 `message` 触发器。
 
 ### 输入与异步时序