fix(commands): harden registry and UI ordering

.agents/notes/implemented/feature/2026-07-19-plugin-command-registration.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
-2026-07-19-plugin-command-registration.md: 5b599358036054c644985474c9c16518fcb5042a
-2026-07-19-plugin-command-registration.zh.md: 08c9e13d122bc56c9feae35244e0f903c3b76b32
+2026-07-19-plugin-command-registration.md: 821f22405fd6a4bc0b8bfd3c5edf773be844899d
+2026-07-19-plugin-command-registration.zh.md: 7a2ed82eb1a8f55d4d701a68c4053e5d412b7d04

.agents/notes/implemented/feature/2026-07-19-plugin-command-registration.md

@@ -26,7 +26,7 @@ A `CommandDefinition` contains a lowercase name without `/`, a non-empty descrip
 
 An unscoped registration is global. A command-injected plugin mounted beneath an agent context inherits that agent's scope key and lifetime, so its definition shadows a same-named global only for that exact agent. The child declares its own `commands` injection because `agent.ctx` intentionally inherits the core agent-loop dependency surface; adding a UI service to the loop merely to enable scoped registration would invert the dependency graph.
 
-Registration and removal emit the unfiltered `commands/change` registry notification. Adapters recompute each live agent's effective view rather than trying to infer which sessions a change affects. Cordis ownership removes definitions when their producer, UI instance, or agent scope unloads, so HMR cannot leave stale discovery entries or handlers.
+Registration and removal emit the unfiltered, non-vetoing `commands/change` registry notification. Adapters recompute each live agent's effective view rather than trying to infer which sessions a change affects. The registry contains and logs each observer failure independently, so a broken UI refresh cannot roll back another plugin's mutation or starve a later observer. Cordis ownership removes definitions when their producer, UI instance, or agent scope unloads, so HMR cannot leave stale discovery entries or handlers.
 
 ### Direct dispatch and cancellation
 
@@ -42,7 +42,7 @@ Each submitted command owns an `AbortController`. TUI disposal aborts outstandin
 
 ### ACP mapping
 
-The bridge follows the current [ACP v1 slash-command contract](https://agentclientprotocol.com/protocol/v1/slash-commands). `session/new` and `session/load` emit the exact agent's full `available_commands_update` snapshot; every registry change emits a replacement snapshot for each live session. Names, descriptions, and optional unstructured-input hints map directly to `AvailableCommand`.
+The bridge follows the current [ACP v1 slash-command contract](https://agentclientprotocol.com/protocol/v1/slash-commands). `session/new` and `session/load` emit the exact agent's full `available_commands_update` snapshot; a new session's RPC response introduces its server-generated id before the snapshot is enqueued. Every registry change emits a replacement snapshot for each live session. Names, descriptions, and optional unstructured-input hints map directly to `AvailableCommand`.
 
 ACP permits a command prompt to contain additional supported content blocks. The bridge applies its ordinary lossless `text` and `resource_link` flattening, then enters the command plane when the result starts with `/`. Unsupported prompt blocks are rejected by the existing capability boundary. Known commands execute directly; unknown or malformed slash input returns a direct error and never reaches the model. Successful text, expected errors, and thrown-failure diagnostics stream as live `agent_message_chunk` output and settle `end_turn`.
 
@@ -50,7 +50,7 @@ One model prompt or direct command may be in flight per ACP session, independent
 
 ## Testing
 
-The registry suite covers syntax boundaries, immutable normalization, default and explicit surfaces, deterministic sorting, global and scoped shadowing, duplicate rejection, exact disposal, change-notification rollback, direct invocation, expected and malformed results, synchronous and asynchronous failure, and every abort timing edge at per-file 100% statement, branch, function, and line coverage.
+The registry suite covers syntax boundaries, immutable normalization, runtime metadata validation, default and explicit surfaces, deterministic sorting, global and scoped shadowing, duplicate rejection, exact disposal, contained change-notification failures, direct invocation, expected and malformed results, synchronous and asynchronous failure, and every abort timing edge at per-file 100% statement, branch, function, and line coverage.
 
 TUI tests exercise all migrated built-ins, live plugin discovery, help/autocomplete refresh, direct results, unknown-command rejection, raw-input delivery, definition removal, startup rollback, and disposal cancellation. ACP tests use the real SDK connection, agent factory, loop, and JSONL persistence to verify create/load snapshots, dynamic updates, scoped multi-session catalogs, supported-block flattening, direct success/error/failure, unknown-command isolation, cancellation, and the absence of model requests or session messages. The SDK helper suite pins direct-ACP composition. Keyless ACP and terminal snapshots pin the new protocol and rendered transcript shapes.
 

.agents/notes/implemented/feature/2026-07-19-plugin-command-registration.zh.md

@@ -26,7 +26,7 @@ TUI 拥有七个斜杠命令，而 ACP 定义了标准命令目录与调用形
 
 无作用域注册是全局注册。挂载在智能体上下文之下并注入 `commands` 的插件会继承该智能体的作用域键与生命周期，因此其定义仅为该准确智能体遮蔽同名全局定义。子插件自行声明 `commands` 注入，因为 `agent.ctx` 有意只继承核心智能体循环的依赖界面；仅为了实现作用域注册而让循环依赖 UI 服务会倒置依赖图。
 
-注册和移除会发出未过滤的 `commands/change` 注册表通知。适配器重新计算每个实时智能体的有效视图，而不尝试推断某次变更影响哪些会话。Cordis 所有权会在生产者、UI 实例或智能体作用域卸载时移除定义，因此 HMR 不会留下陈旧的发现项或处理器。
+注册和移除会发出未过滤、不可否决的 `commands/change` 注册表通知。适配器重新计算每个实时智能体的有效视图，而不尝试推断某次变更影响哪些会话。注册表会分别隔离并记录每个观察者失败，因此损坏的 UI 刷新无法回滚另一插件的变更，也无法阻止后续观察者。Cordis 所有权会在生产者、UI 实例或智能体作用域卸载时移除定义，因此 HMR 不会留下陈旧的发现项或处理器。
 
 ### 直接分派与取消
 
@@ -42,7 +42,7 @@ TUI 把 `help`、`clear`、`cancel`、`reasoning`、`tools`、`redraw` 和 `exit
 
 ### ACP 映射
 
-桥接遵循当前的 [ACP v1 斜杠命令契约](https://agentclientprotocol.com/protocol/v1/slash-commands)。`session/new` 与 `session/load` 发出准确智能体的完整 `available_commands_update` 快照；每次注册表变更都会为每个实时会话发出替换快照。名称、描述和可选非结构化输入提示直接映射到 `AvailableCommand`。
+桥接遵循当前的 [ACP v1 斜杠命令契约](https://agentclientprotocol.com/protocol/v1/slash-commands)。`session/new` 与 `session/load` 发出准确智能体的完整 `available_commands_update` 快照；新会话的 RPC 响应会先引入服务端生成的 id，随后快照才会入队。每次注册表变更都会为每个实时会话发出替换快照。名称、描述和可选非结构化输入提示直接映射到 `AvailableCommand`。
 
 ACP 允许命令提示携带额外的受支持内容块。桥接应用普通的无损 `text` 与 `resource_link` 扁平化，然后在结果以 `/` 开头时进入命令平面。不支持的提示块由现有能力边界拒绝。已知命令直接执行；未知或格式错误的斜杠输入返回直接错误，绝不会到达模型。成功文本、预期错误和抛出失败的诊断作为实时 `agent_message_chunk` 输出流式发送，并以 `end_turn` 结束请求。
 
@@ -50,7 +50,7 @@ ACP 允许命令提示携带额外的受支持内容块。桥接应用普通的
 
 ## 测试
 
-注册表测试覆盖语法边界、不可变规范化、默认和显式界面、确定性排序、全局与作用域遮蔽、重复拒绝、准确释放、变更通知回滚、直接调用、预期和格式错误结果、同步与异步失败，以及每种中止时序边沿；该源文件达到逐文件 100% 语句、分支、函数和行覆盖率。
+注册表测试覆盖语法边界、不可变规范化、运行时元数据校验、默认和显式界面、确定性排序、全局与作用域遮蔽、重复拒绝、准确释放、变更通知失败隔离、直接调用、预期和格式错误结果、同步与异步失败，以及每种中止时序边沿；该源文件达到逐文件 100% 语句、分支、函数和行覆盖率。
 
 TUI 测试覆盖全部迁移后的内置命令、实时插件发现、帮助与自动补全刷新、直接结果、未知命令拒绝、原始输入交付、定义移除、启动回滚和释放取消。ACP 测试使用真实 SDK 连接、智能体工厂、循环与 JSONL 持久化，验证创建/加载快照、动态更新、作用域多会话目录、受支持块扁平化、直接成功/错误/失败、未知命令隔离、取消，以及不存在模型请求或会话消息。SDK helper 测试固定直接 ACP 组合。无密钥 ACP 与终端快照固定新的协议和渲染记录形态。