docs(user): explain CLI overlay precedence

docs/user/guide/config.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/user/guide/config.md
-config.md: c9c760cbdb9650e608809fee4498b7f884b339dc
-config.zh.md: b80e31c6f77f51d013aaebe5c4e9e43f5819e33f
+config.md: 34a2a902e11fae36b21affc136be70c2e7bd89f9
+config.zh.md: 62d2e35c4501be2cea9d58f2c0d54c3c770e8a08

docs/user/guide/config.md

@@ -48,6 +48,12 @@ A minimal configuration is a list of plugin entries:
 
 Plugins load in file order. Place plugins that depend on services after the applications or capability plugins that provide them. Missing models, tools, and plugins fail as early as possible instead of being silently ignored.
 
+## CLI overlays
+
+The TUI composes `base.cordis.yml` and `tui.cordis.yml`, then applies one optional patch list. By default that final list is `~/.dsh/config.yaml`; `dsh --config <path>` replaces the personal list with the named overlay. `dsh --config-replace <path>` instead boots the named file as the complete tree, without shipped or personal layers. `dsh web --config <path>` adds its overlay after the shared base and Web surface defaults and before Web profile and CLI-flag patches.
+
+A patch replaces a row's entire `config` value; it does not deep-merge keys. For example, patching `llm-deepseek` with only `config: { thinking: disabled }` also removes that row's configured `apiKey` and `baseURL`, so restate every key the row must retain.
+
 ## JavaScript values and environment variables
 
 The Cordis loader evaluates runtime expressions tagged with `!!js`. Keep API keys and other secrets in the gitignored `.env` file at the repository root, never in committed configuration.

docs/user/guide/config.zh.md

@@ -48,6 +48,12 @@ Harness 使用 `cordis.yml` 描述 Agent 加载哪些插件以及每个插件的
 
 插件按文件中的顺序加载。依赖其他服务的插件应该排在提供这些服务的应用或能力插件之后；引用不存在的模型、工具或插件会尽早报错，而不是被静默忽略。
 
+## CLI 覆盖层
+
+TUI 先组合 `base.cordis.yml` 与 `tui.cordis.yml`，再应用一个可选补丁列表。默认的最后一层是 `~/.dsh/config.yaml`；`dsh --config <path>` 会以指定覆盖替代个人补丁列表。`dsh --config-replace <path>` 则把指定文件作为完整配置树启动，不使用已交付配置或个人层。`dsh web --config <path>` 会在共享基础配置与 Web 界面默认值之后、Web profile 与命令行标志补丁之前添加覆盖。
+
+补丁会替换目标行的整个 `config` 值，而不是深度合并各个键。例如，只用 `config: { thinking: disabled }` 修补 `llm-deepseek`，也会移除该行原有的 `apiKey` 与 `baseURL`；因此必须重新写出该行需要保留的全部键。
+
 ## JavaScript 值和环境变量
 
 Cordis loader 使用 `!!js` 标签读取运行时表达式。API key 等凭据应放在仓库根目录、已被 Git 忽略的 `.env` 中，不能提交到配置文件。