fix(pty): close provider cancellation races

docs/core-data-structures/subprocess.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/subprocess.md
-subprocess.md: 89c75aea3393a000612e3b8f87d263c7b4fa7c60
-subprocess.zh.md: 83fb44f4750ba31db1f4336c0c293eb9e236be22
+subprocess.md: 95e9454a75112cf98e1ed583f970c50fe90aac37
+subprocess.zh.md: 58127d662fa599d19f632449d42b8aa3259886d6

docs/core-data-structures/subprocess.md

@@ -240,7 +240,7 @@ interface SubprocessOutcome {
 
 ## Terminal-process primitive
 
-`spawnTerminal(spec)` is the non-pipe process primitive. The provider allocates the controlling terminal and owns UTF-8 text transport, foreground-process-group inspection and signalling, and one awaited TERM-to-KILL operation that reaches whole-session quiescence. The PTY backend remains responsible for prompt detection, readiness inference, scrollback, sandbox policy, and persistent-session ownership; ordinary `spawn()` cannot reconstruct controlling-terminal semantics.
+`spawnTerminal(spec)` is the non-pipe process primitive. The provider allocates the controlling terminal and owns UTF-8 text transport, foreground-process-group inspection and signalling, and one awaited TERM-to-KILL operation that reaches quiescence for every session member the provider can still observe; providers document substrate-specific observability limits. The PTY backend remains responsible for prompt detection, readiness inference, scrollback, sandbox policy, and persistent-session ownership; ordinary `spawn()` cannot reconstruct controlling-terminal semantics.
 
 The terminal spec fully specifies argv, cwd, environment overrides, dimensions, cleanup grace, and optional allocation cancellation. Its handle exposes `pid`, ordered output, `done`, `write`, `inspectForeground`, `signalForeground`, and awaited `terminate`; the exact public shapes are generated into the [`ctx.subprocess` service catalog](../cordis-catalog/services.md#ctxsubprocess--subprocessservice-abstract-seam).
 

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

@@ -240,7 +240,7 @@ interface SubprocessOutcome {
 
 ## 终端进程原语
 
-`spawnTerminal(spec)` 是非管道进程原语。提供方分配控制终端，并负责 UTF-8 文本传输、前台进程组检查与信号发送，以及一项须等待的 TERM→KILL 操作；该操作会使整个会话完全停稳。PTY 后端仍负责提示符检测、就绪推断、scrollback、沙箱策略和持久会话所有权；普通 `spawn()` 无法重建控制终端语义。
+`spawnTerminal(spec)` 是非管道进程原语。提供方分配控制终端，并负责 UTF-8 文本传输、前台进程组检查与信号发送，以及一项须等待的 TERM→KILL 操作；该操作会使提供方仍可观察到的每个会话成员完全停稳，提供方则会记录执行基底特有的可观察性限制。PTY 后端仍负责提示符检测、就绪推断、scrollback、沙箱策略和持久会话所有权；普通 `spawn()` 无法重建控制终端语义。
 
 终端 spec 完全指定 argv、cwd、环境覆盖、尺寸、清理宽限期与可选的分配取消。其句柄公开 `pid`、有序输出、`done`、`write`、`inspectForeground`、`signalForeground` 和须等待的 `terminate`；确切的公共形状生成到 [`ctx.subprocess` 服务目录](../cordis-catalog/services.md#ctxsubprocess--subprocessservice-abstract-seam)中。