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

# Conflicts:
#	.agents/notes/implemented/feature/2026-07-06-sandbox.i18n.yaml
#	.agents/notes/implemented/feature/2026-07-06-sandbox.md
#	.agents/notes/implemented/feature/2026-07-06-sandbox.zh.md
#	packages/host/apiproxy/README.i18n.yaml

docs/core-data-structures/sandbox.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/sandbox.md
-sandbox.md: 9bc05fa06f22fdc9ac9e8aacd482c1e7c2f2edec
-sandbox.zh.md: ff44db13115073f3a77d2bda575cc91ec41da418
+sandbox.md: b931dca54afd1fdd1dcba5b8e7778feeedb7d15d
+sandbox.zh.md: a2334148e0237db2309c77437cf0681586e2fb5a

docs/core-data-structures/sandbox.md

@@ -87,7 +87,27 @@ interface SandboxPolicy extends SandboxExecutionPolicy {
 
 ## Wrapped argv and classification dialects
 
-`ConfinedArgv` is what the consumer spawns. Besides the replacement argv, it carries the backend's enforcement fact and two orthogonal stderr dialects. `denialSignatures` identify the confined command being blocked while the sandbox works correctly. `runnerFailureSignatures` identify the sandbox runner refusing or failing before it executes the command; consumers check these first and surface a sandbox infrastructure failure, never an ordinary task failure.
+`RunnerFailureRule` combines evidence that a runner failed before executing the command. A consumer requires a nonzero exit, the optional allowed-exit-code gate, and a case-insensitive fatal signature within one remaining stderr line. Case-insensitive exact full-line informational exclusions are removed first, so a benign runner notice cannot prove failure by itself. The matched line remains available as error detail; classification does not rewrite stderr.
+
+```ts type-equiv
+/**
+ * Evidence that identifies a sandbox runner failing before it executes the
+ * wrapped command. A consumer first applies {@link allowedExitCodes} when
+ * present, removes {@link informationalLines} by case-insensitive exact line
+ * equality, then matches {@link fatalSignatures} case-insensitively within
+ * each remaining stderr line. Exit status alone never proves runner failure.
+ */
+interface RunnerFailureRule {
+  /** Nonzero process exit codes on which this rule may match; omitted permits any nonzero exit. */
+  allowedExitCodes?: readonly number[]
+  /** Non-empty substrings identifying a fatal runner diagnostic on one stderr line. */
+  fatalSignatures: readonly string[]
+  /** Benign stderr lines excluded by exact full-line equality before fatal matching. */
+  informationalLines?: readonly string[]
+}
+```
+
+`ConfinedArgv` is what the consumer spawns. Besides the replacement argv, it carries the backend's enforcement fact and two orthogonal stderr classifiers. `denialSignatures` identify the confined command being blocked while the sandbox works correctly. `runnerFailureRules` identify the sandbox runner refusing or failing before it executes the command; consumers check these first and surface a sandbox infrastructure failure, never an ordinary task failure.
 
 ```ts type-equiv
 /**
@@ -110,18 +130,19 @@ interface ConfinedArgv {
    */
   denialSignatures: readonly string[]
   /**
-   * Case-insensitive signatures for runner failure before command execution.
-   * Consumers check these before denial signatures: runner failure means the
+   * Structured runner-failure evidence rules. Consumers require a matching
+   * fatal stderr line (after informational exclusions) and any rule-specific
+   * exit-code gate before checking denial signatures: runner failure means the
    * command never ran, while denial means confinement worked and blocked it.
    */
-  runnerFailureSignatures: readonly string[]
+  runnerFailureRules: readonly RunnerFailureRule[]
 }
 ```
 
-An operator-configured local runner must supply at least one `runnerFailureSignatures` entry for its own pre-exec refusal dialect; the provider adds outer-shell missing and unexecutable forms automatically. This makes an executable custom runner rejecting its profile distinguishable from the wrapped command exiting with the same status.
+The operator-facing local-provider key remains `runnerFailureSignatures`: an operator-configured runner must supply at least one non-empty, single-line, case-insensitive substring for its own pre-exec refusal dialect. The provider maps those entries into one rule. Consumers directly spawn `ConfinedArgv.argv`, so a missing runner, a non-executable runner, or an executable script whose shebang interpreter is unavailable rejects through the spawn channel rather than a stderr rule when Node supplies attributable `ENOENT`/`EACCES` evidence; after a process starts, child exits such as 126 or 127 remain ordinary unless the selected runner's documented fatal signature matches.
 
 ## Provider and fail-closed errors
 
-`ctx.sandbox.confine(argv, policy)` returns a `ConfinedArgv` or throws `SandboxUnavailableError` with code `SANDBOX_UNAVAILABLE` when no usable backend exists. A selected runner can also fail closed at execution time, in which case its failure signature carries the same infrastructure meaning. Silent unconfined passthrough is never legal for a confined policy.
+`ctx.sandbox.confine(argv, policy)` returns a `ConfinedArgv` or throws `SandboxUnavailableError` with code `SANDBOX_UNAVAILABLE` when no usable backend exists. Any direct spawn rejection of the returned argv proves the confined launch never started, but only `ENOENT` or `EACCES` with positive Node provenance for provider argv[0] after the caller-owned workdir is independently verified usable carries infrastructure meaning and the original error as detail. A bare `syscall: 'spawn'` without an exact error path, any other code, an invalid or unusable workdir, a resource failure, an unrelated syscall, or an unstructured rejection retains the consumer's ordinary command-start semantics. After a process starts, a matching structured rule identifies a runner refusal. Silent unconfined passthrough is never legal for a confined policy.
 
 Provider probing arbitrates between multiple candidates and is cached for the provider lifetime. A platform with one candidate may select it directly; execution-time refusal retains the safety property. The local provider reports bwrap and Seatbelt as full and preserves the Landlock launcher's full/partial kernel verdict.

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

@@ -87,7 +87,27 @@ interface SandboxPolicy extends SandboxExecutionPolicy {
 
 ## 包装后的 argv 与分类方言
 
-`ConfinedArgv` 是消费方实际 spawn 的内容。除了替换后的 argv，它还携带后端的强制执行事实和两种正交的 stderr 方言。`denialSignatures` 用于识别沙箱正常工作、受限命令被阻止的情况。`runnerFailureSignatures` 用于识别沙箱运行器在执行命令之前拒绝或失败的情况；消费方应先检查后者，将其作为沙箱基础设施故障上报，而非普通任务失败。
+`RunnerFailureRule` 汇集用于判定 runner 在执行命令前失败的证据。消费方要求进程以非零状态退出，并同时满足可选的允许退出码门控，以及余下某一 stderr 行中不区分大小写的致命签名。系统会先按不区分大小写的整行精确匹配移除信息性排除项，因此无害的 runner 通知本身不能证明失败。匹配到的行仍可用作错误详情；分类过程不会重写 stderr。
+
+```ts type-equiv
+/**
+ * Evidence that identifies a sandbox runner failing before it executes the
+ * wrapped command. A consumer first applies {@link allowedExitCodes} when
+ * present, removes {@link informationalLines} by case-insensitive exact line
+ * equality, then matches {@link fatalSignatures} case-insensitively within
+ * each remaining stderr line. Exit status alone never proves runner failure.
+ */
+interface RunnerFailureRule {
+  /** Nonzero process exit codes on which this rule may match; omitted permits any nonzero exit. */
+  allowedExitCodes?: readonly number[]
+  /** Non-empty substrings identifying a fatal runner diagnostic on one stderr line. */
+  fatalSignatures: readonly string[]
+  /** Benign stderr lines excluded by exact full-line equality before fatal matching. */
+  informationalLines?: readonly string[]
+}
+```
+
+`ConfinedArgv` 是消费方实际 spawn 的内容。除了替换后的 argv，它还携带后端的强制执行事实和两种正交的 stderr 分类器。`denialSignatures` 用于识别沙箱正常工作时受限命令被阻止的情况。`runnerFailureRules` 用于识别沙箱 runner 在执行命令之前拒绝或失败的情况；消费方应先检查后者，将其作为沙箱基础设施故障上报，而非普通任务失败。
 
 ```ts type-equiv
 /**
@@ -110,18 +130,19 @@ interface ConfinedArgv {
    */
   denialSignatures: readonly string[]
   /**
-   * Case-insensitive signatures for runner failure before command execution.
-   * Consumers check these before denial signatures: runner failure means the
+   * Structured runner-failure evidence rules. Consumers require a matching
+   * fatal stderr line (after informational exclusions) and any rule-specific
+   * exit-code gate before checking denial signatures: runner failure means the
    * command never ran, while denial means confinement worked and blocked it.
    */
-  runnerFailureSignatures: readonly string[]
+  runnerFailureRules: readonly RunnerFailureRule[]
 }
 ```
 
-运维人员配置的本地运行器必须为自身的 pre-exec 拒绝方言提供至少一条 `runnerFailureSignatures` 条目；提供方会自动添加外层 shell 报告的「命令不存在」和「不可执行」形式。这使得可执行的自定义运行器拒绝其 profile 的情况能够与被包装命令以相同状态码退出的情况区分开来。
+面向运维人员的本地提供方配置键仍为 `runnerFailureSignatures`：运维人员配置的 runner 必须为自身的 pre-exec 拒绝方言提供至少一个非空、单行、不区分大小写的子串。提供方会将这些条目映射到一条规则。消费方直接 spawn `ConfinedArgv.argv`，因此当 Node 提供可归因的 `ENOENT`／`EACCES` 证据时，缺失的 runner、不可执行的 runner，或 shebang 解释器不可用的可执行脚本会在 spawn 通道遭拒，而不是由 stderr 规则判定；进程启动后，126 或 127 等子进程退出码仍按普通结果处理，除非匹配所选 runner 文档所定义的致命签名。
 
 ## 提供方与 fail-closed 错误
 
-`ctx.sandbox.confine(argv, policy)` 返回一个 `ConfinedArgv`，或在没有可用后端时抛出 `SandboxUnavailableError`（错误码 `SANDBOX_UNAVAILABLE`）。已选定的运行器也可能在执行时 fail-closed，此时其失败签名承载相同的基础设施含义。对于受限策略，静默的无隔离透传永远不合法。
+`ctx.sandbox.confine(argv, policy)` 返回一个 `ConfinedArgv`，或在没有可用后端时抛出 `SandboxUnavailableError`（错误码 `SANDBOX_UNAVAILABLE`）。直接 spawn 所返回的 argv 时，任何拒绝都能证明受限启动从未开始；但只有在调用方拥有的 workdir 经独立验证可用，且 `ENOENT` 或 `EACCES` 带有明确指向提供方 argv[0] 的 Node 来源信息时，该拒绝才具有基础设施含义，并以原始错误作为详细信息。没有精确错误路径的裸 `syscall: 'spawn'`、任何其他错误码、无效或不可用的 workdir、资源失败、无关 syscall 或无结构拒绝仍保留消费方的普通命令启动语义。进程启动后，匹配到的结构化规则标识 runner 拒绝。对于受限策略，静默的无隔离透传永远不合法。
 
 提供方探测在多个候选后端之间仲裁，结果在提供方生命周期内缓存。只有一个候选后端的平台可以直接选定它；执行时拒绝仍保留安全属性。本地提供方将 bwrap 和 Seatbelt 报告为 full，并保留 Landlock 启动器的 full/partial 内核裁定。