feat(loader): interpolate the entry disabled field

The Windows platform layer disables tool-bash and inserts the pwsh stack, but the shipped presets each mount a tool-bash row that re-enabled the tool on win32 — the session had both a PowerShell-backed bash tool and tool-pwsh, silently, because no spec pinned the composed preset layer.

The Loader now evaluates a disabled: !!js expression against the loader context at every mount decision; disabled is the only interpolated metadata field, and the raw node stays in the options so write-back keeps the !!js form. The standard/code/cordis presets gate tool-bash with process.platform === 'win32', verify-cordis-config allows expressions in disabled only, and the windows-shell spec pins the preset-level invariant.

docs/cordis-primer.zh.md

@@ -39,7 +39,7 @@ Cordis 是 DeepSeek Harness SDK 底层以 vendor 方式引入的插件框架。
 
 ## Loader 配置
 
-`@deepseek-ai/cordis-plugin-include` 将 `!!js` 解析为表达式节点。Loader 只在声明的注入激活后，基于该插件上下文（`ctx.serviceName`）插值条目的 `config`；Include 会保留嵌套行表达式，直到目标行激活。条目元数据（`id`、`name`、`group`、`disabled`、`inject`、`intercept`、`isolate`）保持字面值，因此 `disabled: !!js ...` 始终禁用该条目。由环境选择插件时，请使用 overlay。
+`@deepseek-ai/cordis-plugin-include` 将 `!!js` 解析为表达式节点。Loader 在声明的注入激活后，基于该插件上下文（`ctx.serviceName`）插值条目的 `config`，并在每次挂载决策时基于 loader 上下文插值其 `disabled` 字段；Include 会保留嵌套行表达式，直到目标行激活。其余条目元数据保持字面值。由环境选择插件时，请使用 overlay。
 
 ## 实践规则