build(vendor): rescope the vendored Cordis packages into @deepseek-ai

Machine-produced by `pnpm run rescope-vendor --apply` plus the regeneration it
prints: `pnpm install` for the lockfile, `pnpm run gen-third-party-notices`,
`verify-translation-pairing --write` for the touched bilingual pairs,
`gen-doc-graphs`, and one typert snapshot whose ids embed character offsets.
`pnpm run rescope-vendor --check` verifies the result.

Renames nine vendored packages (cordis, cosmokit, schemastery and the six
@cordisjs plugins) and every reference that resolves them: manifest names and
dependency keys, module specifiers including declare-module merges, cordis.yml
plugin names, tsconfig paths, every Markdown fence, and `docs/` prose.
Directory names, upstream versions, and dependency ranges are unchanged, so
vendor/README.md still reads as an upstream snapshot; its manifest table gains
an upstream-name column so THIRD_PARTY_NOTICES keeps MIT attribution pointed
at each fork's origin.

The tutorial tier follows the rename end to end: its yaml fences named plugins
the Loader can no longer resolve, its `ts ignore-check` fences disagreed with
the compiled fences beside them, and its prose quoted both. The contracts that
told readers to keep upstream names — the root convention and the vendoring
cookbook's tree comment and manifest invariant — now say to rescope instead.

Two rules read `@deepseek-ai/` as "another workspace plugin": the client bundle
purity gate now names the vendored libraries a browser bundle inlines, and the
files where a bare `cordis` is an agent-preset id keep that product data.

packages/fs/fs-policy/README.zh.md

@@ -5,7 +5,7 @@
 **fs-policy 插件**：它记录观测到的存在或缺失状态，并在 `ctx.fs` 提供方约定（[`@deepseek-ai/dsh-fs`](../fs)）之上增加编辑前读取和带防护的写入/编辑；它通过 `fs/*` 事件门禁参与，**不是**通过方法服务。该插件**不**注册 `ctx.fsPolicy` 服务，也没有公开的 `read`/`write`/`edit`/`resolve` 方法。它是文件系统栈的政策层：不是可替换 seam，而是不应位于 `FileSystem` 提供方基类上的政策。
 
 ```ts
-import type { Context } from 'cordis'
+import type { Context } from '@deepseek-ai/cordis'
 import * as FsPolicy from '@deepseek-ai/dsh-fs-policy'
 
 declare const ctx: Context