feat(host): adaptive directory-picker default via -auto chooser

Add @deepseek-ai/dsh-host-directory-picker-auto, a node-half-only chooser
that samples the host situation once at boot (bind host via a new
httpServer.host getter, SSH markers, platform, DISPLAY/WAYLAND_DISPLAY)
and mounts the matching dual-face backend (-native or -browse) as a real
Loader entry in the in-memory root tree; the effect disposer removes it.
Entry-level mounting keeps the seam's one-row-swaps-both-faces invariant:
the client module table discovers the mounted backend's browser half
exactly as a config row's. apps/cli now composes -auto as its
directory-picker row; composing a backend row directly remains the pin.

packages/host/directory-picker-auto/README.i18n.yaml

@@ -0,0 +1,6 @@
+# Bilingual-pair consistency record (docs/i18n/README.md): the git blob hash of each
+# 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 packages/host/directory-picker-auto/README.md
+README.md: 73692d1fb5af1e7b23b2a99d0a5cd48507f68ce5
+README.zh.md: 5bc9ced01f86d021db256df2c9e69e97ec6a7ab1

packages/host/directory-picker-auto/README.md

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+# @deepseek-ai/dsh-host-directory-picker-auto
+
+English | [中文](README.zh.md)
+
+The **adaptive chooser** of the [directory-picker seam](../directory-picker/README.md): a node-half-only plugin that resolves the host's situation once at boot and mounts the matching dual-face backend — [`-native`](../directory-picker-native/README.md) or [`-browse`](../directory-picker-browse/README.md) — as a real Loader entry in the in-memory root tree (never persisted to a config file; the root tree's `write()` is a no-op). Because the backend arrives as an ordinary entry, its browser half is discovered by the client module table exactly as a config-row's would be, so the seam's one-row-swaps-both-faces invariant holds for the resolved choice. Unloading the chooser removes the entry again, unloading both faces with it.
+
+Resolution is one pure boot-time sample (`resolveDirectoryPickerBackend`), exported for reuse and tests. `native` requires every signal that the operator can see the host display: a loopback-only bind (read from the injected `httpServer`; an all-interfaces bind admits remote browsers no OS chooser can reach), no SSH launch (`SSH_CONNECTION`/`SSH_TTY` unset or blank — under SSH port-forwarding the chooser would open on the unattended server), and a display session (assumed on darwin/win32; `DISPLAY`/`WAYLAND_DISPLAY` elsewhere). Anything ambiguous resolves to `browse`, which works everywhere. The sample happens exactly once per boot so the mounted capability stays stable for the service lifetime, as the seam requires. Pinning an interaction is not a config field here — compose the `-native` or `-browse` row directly instead of this one, the seam's documented swap point; mounting the chooser **and** a backend row together fails loud (duplicate `directoryPicker` service, duplicate client flow in the `single` holes).
+
+## Model Experience
+
+None, as the chooser only composes the GUI host's directory selection; nothing here reaches a model request.
+
+#### KV Cache effect
+
+None; this package neither assembles nor sends a provider request.
+
+## Known Limitations and Deferred Work
+
+- **Detection is a heuristic, not a proof** — a tmux session detached from its SSH launch loses the `SSH_*` markers, and a darwin process outside an Aqua session still counts as displayed; a wrong `native` choice degrades to the backend's existing retryable failure dialog, and composing `-browse` directly pins the safe interaction.
+- **Boot-time only** — one resolution serves every client of the boot; per-connection adaptivity (native for a local browser, browse for a remote one, same server) would need a per-client capability and the wire advertisement the seam deliberately deleted, and waits for a deployment that serves both at once.

packages/host/directory-picker-auto/README.zh.md

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+# @deepseek-ai/dsh-host-directory-picker-auto
+
+[English](README.md) | 中文
+
+[目录选择 seam](../directory-picker/README.md) 的**自适应选择器**：一个只有 node 半侧的插件，在启动时一次性判定宿主处境，并把匹配的双面后端——[`-native`](../directory-picker-native/README.md) 或 [`-browse`](../directory-picker-browse/README.md)——作为真实的 Loader 条目挂进内存根树（绝不持久化到配置文件；根树的 `write()` 是 no-op）。由于后端以普通条目的形式到达，其 browser half 被 client 模块表发现的方式与配置行完全相同，因此对判定出的选择，seam 的“一行同时换两面”不变式依然成立。卸载该选择器会再次移除该条目，连同两面一起卸载。
+
+判定是一次纯函数的启动时采样（`resolveDirectoryPickerBackend`），已导出供复用与测试。`native` 要求“操作者看得到宿主屏幕”的全部信号：仅回环的绑定（从注入的 `httpServer` 读取；全网卡绑定会接入任何 OS 选择器都触及不到的远程浏览器）；非 SSH 启动（`SSH_CONNECTION`／`SSH_TTY` 未设置或为空——SSH 端口转发下选择器会弹在无人值守的服务器上）；以及存在显示会话（darwin／win32 上视为存在，其余平台看 `DISPLAY`／`WAYLAND_DISPLAY`）。任何含糊情形都判定为处处可用的 `browse`。采样每次启动恰好发生一次，因此挂载的能力在服务生命周期内保持稳定，符合 seam 的要求。固定某种交互在这里不是配置字段——直接组合 `-native` 或 `-browse` 行来替代本行，那才是 seam 文档化的切换点；同时挂载选择器**和**某个后端行会大声失败（重复的 `directoryPicker` 服务、`single` 洞中的重复 client 流程）。
+
+## 模型体验
+
+无。该选择器仅组合 GUI 宿主的目录选择；这里没有任何内容进入模型请求。
+
+#### KV 缓存影响
+
+无；该包既不组装也不发送提供方请求。
+
+## 已知限制与延期工作
+
+- **探测是启发式，不是证明**——从 SSH 启动中脱离的 tmux 会话会丢失 `SSH_*` 标记，Aqua 会话之外的 darwin 进程也仍被算作有显示；错误的 `native` 选择会退化为后端既有的可重试失败对话框，而直接组合 `-browse` 即固定住安全的交互。
+- **仅在启动时判定**——一次判定服务本次启动的所有客户端；按连接自适应（同一台服务器，本地浏览器用 native、远程浏览器用 browse）需要按客户端的能力对象以及 seam 有意删除的 wire 广播，等到出现同时服务两种形态的部署再做。

packages/host/directory-picker-auto/package.json

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+{
+  "name": "@deepseek-ai/dsh-host-directory-picker-auto",
+  "description": "Adaptive chooser of the directory-picker seam: resolves the host situation at boot and mounts the native or browse backend for the DeepSeek Harness web GUI host",
+  "version": "0.0.1",
+  "private": true,
+  "type": "module",
+  "main": "lib/index.js",
+  "types": "lib/types/index.d.ts",
+  "exports": {
+    ".": {
+      "types": "./lib/types/index.d.ts",
+      "default": "./lib/index.js"
+    },
+    "./invariant": {
+      "types": "./lib/types/invariant.d.ts",
+      "default": "./lib/invariant.js"
+    },
+    "./src/*": "./src/*",
+    "./package.json": "./package.json"
+  },
+  "files": [
+    "lib/index.js",
+    "lib/invariant.js",
+    "lib/types/**/*.d.ts",
+    "lib/types/**/*.d.ts.map",
+    "src"
+  ],
+  "license": "BSD-3-Clause",
+  "peerDependencies": {
+    "@cordisjs/plugin-loader": "^1.0.0-rc.5",
+    "@deepseek-ai/dsh-host-directory-picker-browse": "^0.0.1",
+    "@deepseek-ai/dsh-host-directory-picker-native": "^0.0.1",
+    "@deepseek-ai/dsh-host-webserver": "^0.0.1",
+    "@deepseek-ai/dsh-invariants": "^0.0.1",
+    "cordis": "^4.0.0-rc.7"
+  },
+  "devDependencies": {
+    "@cordisjs/plugin-include": "workspace:^",
+    "@cordisjs/plugin-loader": "workspace:^",
+    "@deepseek-ai/dsh-host-directory-picker": "workspace:^",
+    "@deepseek-ai/dsh-host-directory-picker-browse": "workspace:^",
+    "@deepseek-ai/dsh-host-directory-picker-native": "workspace:^",
+    "@deepseek-ai/dsh-host-webserver": "workspace:^",
+    "@deepseek-ai/dsh-invariants": "workspace:^",
+    "cordis": "^4.0.0-rc.7"
+  }
+}

packages/host/directory-picker-auto/src/index.ts

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+/**
+ * Adaptive chooser of the directory-picker seam: resolves the host's
+ * situation once at boot (bind host, SSH launch, display session) and mounts
+ * the matching dual-face backend — `-native` or `-browse` — as a real Loader
+ * entry in the in-memory root tree. Because the backend arrives as an
+ * ordinary entry, its browser half is discovered exactly as a config-row's
+ * would be, so the seam's one-row-swaps-both-faces invariant holds for the
+ * resolved choice; pinning an interaction remains composing that backend row
+ * directly instead of this one.
+ * @module @deepseek-ai/dsh-host-directory-picker-auto
+ */
+
+import type { Context } from 'cordis'
+// Empty type imports carry the `loader` and `httpServer` Context merges for the reads below.
+import type {} from '@cordisjs/plugin-loader'
+import type {} from '@deepseek-ai/dsh-host-webserver'
+import type { DirectoryPickerBackendKind } from './resolve.ts'
+import { resolveDirectoryPickerBackend } from './resolve.ts'
+
+export type { DirectoryPickerBackendKind, DirectoryPickerEnv, DirectoryPickerHostFacts } from './resolve.ts'
+export { resolveDirectoryPickerBackend } from './resolve.ts'
+
+/** Cordis plugin name. */
+export const name = 'directory-picker-auto'
+/** Required services: the effective bind host (`httpServer`) and the entry tree the backend mounts into (`loader`). */
+export const inject = ['httpServer', 'loader']
+
+/** Backend package per resolved kind — fixed composition vocabulary, not a tunable. */
+const BACKEND_PACKAGES: Record<DirectoryPickerBackendKind, string> = {
+  native: '@deepseek-ai/dsh-host-directory-picker-native',
+  browse: '@deepseek-ai/dsh-host-directory-picker-browse',
+}
+
+/**
+ * Resolve the backend from one boot-time sample and mount it as a Loader
+ * entry; the effect's disposer removes the entry, so unloading this plugin
+ * unloads both faces of the mounted backend with it.
+ * @param ctx - cordis context carrying the injected `httpServer` and `loader`.
+ */
+export async function apply(ctx: Context): Promise<void> {
+  const backend = resolveDirectoryPickerBackend({
+    bindHost: ctx.httpServer.host,
+    platform: process.platform,
+    env: process.env,
+  })
+  await ctx.effect(async () => {
+    // Root-tree create: the Loader root is in-memory (write() is a no-op), so
+    // the mounted row can never be persisted back into a config file.
+    const id = await ctx.loader.create({ name: BACKEND_PACKAGES[backend] })
+    return () => { ctx.loader.remove(id) }
+  }, 'directory-picker-auto: backend entry')
+}

packages/host/directory-picker-auto/src/invariant.ts

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+/**
+ * Package-owned invariant companion for the adaptive directory-picker chooser.
+ * @module @deepseek-ai/dsh-host-directory-picker-auto/invariant
+ */
+
+import type { Context } from 'cordis'
+import type { InvariantInstaller } from '@deepseek-ai/dsh-invariants'
+
+const PACKAGE_NAME = '@deepseek-ai/dsh-host-directory-picker-auto'
+
+/** Cordis companion plugin name. */
+export const name = 'host-directory-picker-auto-invariant'
+/** Service required before the companion can reserve package ownership. */
+export const inject = ['invariants']
+
+/** No runtime invariant: the sole effect is one boot-time Loader-entry mount owned by the plugin fiber; the store is authoritative. */
+const install: InvariantInstaller = () => {}
+
+/**
+ * Register the adaptive directory-picker invariant companion.
+ * @param ctx - Cordis context carrying the invariant service.
+ * @returns the installed registration's disposer after setup succeeds.
+ */
+export const apply = (ctx: Context): Promise<() => void> =>
+  Promise.resolve(ctx.invariants.register(PACKAGE_NAME, install))

packages/host/directory-picker-auto/src/resolve.ts

@@ -0,0 +1,46 @@
+/**
+ * Boot-time backend resolution for the adaptive directory-picker composition:
+ * one pure decision from sampled host facts to a concrete backend kind. The
+ * caller samples exactly once per boot, so the mounted capability stays
+ * stable for the service lifetime as the seam requires.
+ * @module @deepseek-ai/dsh-host-directory-picker-auto/resolve
+ */
+
+/** Concrete interaction backend the resolver chooses between. */
+export type DirectoryPickerBackendKind = 'native' | 'browse'
+
+/** Environment keys the resolution reads (a `process.env` subset). */
+export type DirectoryPickerEnv = Readonly<
+  Partial<Record<'SSH_CONNECTION' | 'SSH_TTY' | 'DISPLAY' | 'WAYLAND_DISPLAY', string>>
+>
+
+/** Host facts the backend choice is a pure function of, sampled once at boot. */
+export interface DirectoryPickerHostFacts {
+  /** Effective webserver bind host (`127.0.0.1` or `0.0.0.0`). */
+  bindHost: string
+  /** Host process platform. */
+  platform: NodeJS.Platform
+  /** Environment sample; SSH marks a remote operator, DISPLAY/WAYLAND_DISPLAY a Linux display. */
+  env: DirectoryPickerEnv
+}
+
+/** An env value counts only when set and non-blank (an empty export is "unset" by shell convention). */
+const present = (value: string | undefined): boolean => value !== undefined && value !== ''
+
+/**
+ * Resolve which backend serves this boot. `native` requires every signal that
+ * the operator can see the host display: a loopback-only bind (an
+ * all-interfaces bind admits remote browsers no OS chooser can reach), no SSH
+ * launch (under SSH port-forwarding the chooser would open on the unattended
+ * server), and a display session (assumed on darwin/win32, `DISPLAY`/
+ * `WAYLAND_DISPLAY` elsewhere). Anything ambiguous resolves to `browse`,
+ * which works everywhere.
+ * @param facts - the sampled host facts.
+ * @returns the backend kind to mount.
+ */
+export function resolveDirectoryPickerBackend(facts: DirectoryPickerHostFacts): DirectoryPickerBackendKind {
+  if (facts.bindHost !== '127.0.0.1') return 'browse'
+  if (present(facts.env.SSH_CONNECTION) || present(facts.env.SSH_TTY)) return 'browse'
+  if (facts.platform === 'darwin' || facts.platform === 'win32') return 'native'
+  return present(facts.env.DISPLAY) || present(facts.env.WAYLAND_DISPLAY) ? 'native' : 'browse'
+}

packages/host/directory-picker-auto/tests/loader-composition.spec.ts

@@ -0,0 +1,139 @@
+/**
+ * REAL-composition coverage: a test-only cordis.yml booted through the
+ * vendored Loader mounts the webserver row plus the adaptive chooser, and the
+ * assertions observe the durable outcome — which backend entry the chooser
+ * mounted into the Loader store, the capability the seam then serves, and
+ * that disposing the chooser removes the mounted entry again (HMR safety).
+ */
+
+import { mkdir, mkdtemp, readFile, rm, writeFile } from 'node:fs/promises'
+import { tmpdir } from 'node:os'
+import { join } from 'node:path'
+import { pathToFileURL } from 'node:url'
+import { afterEach, describe, expect, it, vi } from 'vitest'
+import { Context } from 'cordis'
+import Loader from '@cordisjs/plugin-loader'
+import Include from '@cordisjs/plugin-include'
+import HttpServer from '@deepseek-ai/dsh-host-webserver'
+import type { DirectoryPicker } from '@deepseek-ai/dsh-host-directory-picker'
+import BrowseDirectoryPicker from '@deepseek-ai/dsh-host-directory-picker-browse'
+import NativeDirectoryPicker from '@deepseek-ai/dsh-host-directory-picker-native'
+import * as DirectoryPickerAuto from '../src/index.ts'
+
+const AUTO = '@deepseek-ai/dsh-host-directory-picker-auto'
+const NATIVE = '@deepseek-ai/dsh-host-directory-picker-native'
+const BROWSE = '@deepseek-ai/dsh-host-directory-picker-browse'
+
+let root: string | undefined
+let context: Context | undefined
+
+afterEach(async () => {
+  vi.unstubAllEnvs()
+  await context?.fiber.dispose()
+  context = undefined
+  if (root !== undefined) await rm(root, { recursive: true, force: true })
+  root = undefined
+})
+
+/** Write a dist fixture and a two-row cordis.yml (webserver + chooser), then boot it through the real Loader. */
+async function loadComposition(bindHost: '127.0.0.1' | '0.0.0.0'): Promise<{ ctx: Context; configPath: string }> {
+  root = await mkdtemp(join(tmpdir(), 'dsh-directory-picker-auto-'))
+  const dist = join(root, 'dist')
+  await mkdir(dist)
+  const distIndex = join(dist, 'index.html')
+  await writeFile(distIndex, '<head></head><body>shell</body>')
+  const configPath = join(root, 'cordis.yml')
+  await writeFile(configPath, [
+    "- name: '@deepseek-ai/dsh-host-webserver'",
+    '  config:',
+    `    host: '${bindHost}'`,
+    '    port: 0',
+    `    distIndex: '${distIndex}'`,
+    `- name: '${AUTO}'`,
+    '',
+  ].join('\n'))
+
+  context = new Context()
+  context.baseUrl = pathToFileURL(root).href + '/'
+  await context.plugin(Loader)
+  context.loader.builtins.include = Include
+  const modules = new Map<string, unknown>([
+    ['@deepseek-ai/dsh-host-webserver', HttpServer],
+    [AUTO, DirectoryPickerAuto],
+    [NATIVE, NativeDirectoryPicker],
+    [BROWSE, BrowseDirectoryPicker],
+  ])
+  context.loader.internal = {
+    version: 'v2',
+    async import(specifier: string) {
+      if (!modules.has(specifier)) throw new Error(`unexpected Loader import: ${specifier}`)
+      return modules.get(specifier)
+    },
+  } as unknown as NonNullable<typeof context.loader.internal>
+  await context.loader.create({
+    name: 'cordis:include',
+    config: { path: pathToFileURL(configPath).href },
+  })
+  await context.loader.await()
+  return { ctx: context, configPath }
+}
+
+/** Entry names currently present in the loader store (root tree plus subtrees). */
+function entryNames(ctx: Context): string[] {
+  return [...ctx.loader.entries()].map(entry => entry.options.name)
+}
+
+/** Force every signal of an attended host: no SSH launch, a display on any platform. */
+function stubAttendedHost(): void {
+  vi.stubEnv('SSH_CONNECTION', '')
+  vi.stubEnv('SSH_TTY', '')
+  vi.stubEnv('DISPLAY', ':0')
+}
+
+describe('real Loader composition', () => {
+  // Real-Loader composition resolves workspace packages through tsx at test
+  // time; first resolution after the host/client program split is slow enough
+  // to trip the default 5s budget on cold caches.
+  it('mounts the native backend for an attended loopback host and unmounts it on disposal', { timeout: 60_000 }, async () => {
+    stubAttendedHost()
+    const { ctx, configPath } = await loadComposition('127.0.0.1')
+
+    const unloaded = [...ctx.loader.entries()]
+      .filter(entry => entry.fiber === undefined && !entry.disabled)
+      .map(entry => entry.options.name)
+    expect(unloaded).toEqual([])
+    expect(entryNames(ctx)).toContain(NATIVE)
+    expect(entryNames(ctx)).not.toContain(BROWSE)
+    const picker = ctx.get('directoryPicker') as DirectoryPicker
+    expect(picker.capability().kind).toBe('native')
+    // The mounted row lives in the Loader's in-memory root tree only — the
+    // booted config file must never gain the resolved backend row.
+    expect(await readFile(configPath, 'utf8')).not.toContain(NATIVE)
+
+    // HMR safety: disposing the chooser's fiber removes the entry it created.
+    const autoEntry = [...ctx.loader.entries()].find(entry => entry.options.name === AUTO)!
+    await autoEntry.fiber!.dispose()
+    await ctx.loader.await()
+    expect(entryNames(ctx)).not.toContain(NATIVE)
+    expect(ctx.get('directoryPicker')).toBeUndefined()
+  })
+
+  it('mounts the browse backend under an SSH launch', { timeout: 60_000 }, async () => {
+    stubAttendedHost()
+    vi.stubEnv('SSH_CONNECTION', '10.0.0.2 55 10.0.0.9 22')
+    const { ctx } = await loadComposition('127.0.0.1')
+
+    expect(entryNames(ctx)).toContain(BROWSE)
+    expect(entryNames(ctx)).not.toContain(NATIVE)
+    const picker = ctx.get('directoryPicker') as DirectoryPicker
+    expect(picker.capability().kind).toBe('browse')
+  })
+
+  it('mounts the browse backend for an all-interfaces bind even on an attended host', { timeout: 60_000 }, async () => {
+    stubAttendedHost()
+    const { ctx } = await loadComposition('0.0.0.0')
+
+    expect(entryNames(ctx)).toContain(BROWSE)
+    expect(entryNames(ctx)).not.toContain(NATIVE)
+  })
+})

packages/host/directory-picker-auto/tests/resolve.spec.ts

@@ -0,0 +1,37 @@
+import { describe, expect, it } from 'vitest'
+import { resolveDirectoryPickerBackend } from '../src/resolve.ts'
+import type { DirectoryPickerHostFacts } from '../src/resolve.ts'
+
+/** Baseline facts that resolve to `native`; each case overrides one signal. */
+const attended: DirectoryPickerHostFacts = {
+  bindHost: '127.0.0.1',
+  platform: 'darwin',
+  env: {},
+}
+
+describe('resolveDirectoryPickerBackend', () => {
+  it('resolves native for a loopback bind on a display platform', () => {
+    expect(resolveDirectoryPickerBackend(attended)).toBe('native')
+    expect(resolveDirectoryPickerBackend({ ...attended, platform: 'win32' })).toBe('native')
+  })
+
+  it('resolves browse for an all-interfaces bind regardless of other signals', () => {
+    expect(resolveDirectoryPickerBackend({ ...attended, bindHost: '0.0.0.0' })).toBe('browse')
+  })
+
+  it('resolves browse under an SSH launch (either env marker)', () => {
+    expect(resolveDirectoryPickerBackend({ ...attended, env: { SSH_CONNECTION: '10.0.0.2 55 10.0.0.9 22' } })).toBe('browse')
+    expect(resolveDirectoryPickerBackend({ ...attended, env: { SSH_TTY: '/dev/pts/3' } })).toBe('browse')
+  })
+
+  it('requires a display session on platforms without an implied one', () => {
+    expect(resolveDirectoryPickerBackend({ ...attended, platform: 'linux' })).toBe('browse')
+    expect(resolveDirectoryPickerBackend({ ...attended, platform: 'linux', env: { DISPLAY: ':0' } })).toBe('native')
+    expect(resolveDirectoryPickerBackend({ ...attended, platform: 'linux', env: { WAYLAND_DISPLAY: 'wayland-1' } })).toBe('native')
+  })
+
+  it('treats blank env exports as unset', () => {
+    expect(resolveDirectoryPickerBackend({ ...attended, env: { SSH_CONNECTION: '', SSH_TTY: '' } })).toBe('native')
+    expect(resolveDirectoryPickerBackend({ ...attended, platform: 'linux', env: { DISPLAY: '', WAYLAND_DISPLAY: '' } })).toBe('browse')
+  })
+})

packages/host/directory-picker-auto/tsconfig.json

@@ -0,0 +1,27 @@
+{
+  "extends": "../../../tsconfig.base.json",
+  "compilerOptions": {
+    "rootDir": "src",
+    "outDir": "lib/types"
+  },
+  "include": [
+    "src"
+  ],
+  "references": [
+    {
+      "path": "../../../vendor/cosmokit"
+    },
+    {
+      "path": "../../../vendor/cordis"
+    },
+    {
+      "path": "../../../vendor/loader"
+    },
+    {
+      "path": "../webserver"
+    },
+    {
+      "path": "../../support/invariants"
+    }
+  ]
+}