目录选择器截断含「开」等字符的路径：dsh-host-directory-picker-native: native picker truncates paths containing chars with 0x00 low byte (e.g. 开 U+5F00)

[devwangrui]

Environment

• Package: @deepseek-ai/dsh-host-directory-picker-native@0.1.0-rc.6
• DSH: 0.1.0-rc.6
• Platform: Windows (win32)

Summary

readUtf16 in packages/host/directory-picker-native/src/win32-dialog-bindings.ts
only checks the LOW byte of each UTF-16 code unit for the NUL terminator. Any
character whose code point is a multiple of 256 (low byte 0x00) is mistaken for
the string terminator, truncating the selected path.

Reproduce

1. On Windows, create a folder named 海康开放平台 (contains 开 = U+5F00).
2. Add a workspace, select that folder in the native picker, confirm.
3. Workspace creation fails with:
   workspace-invalid-path: cannot create a workspace at "D:\视频播放\海康":
   ENOENT: no such file or directory, realpath 'D:\视频播放\海康'

The path is truncated at 开 (dropping 开放平台).

Root cause

packages/host/directory-picker-native/src/win32-dialog-bindings.ts:40

while (end + 1 < bytes.length && bytes[end] !== 0) end += 2

This checks only bytes[end] (the low byte). A UTF-16LE NUL terminator is
0x0000 (both bytes zero), but 开 (U+5F00) encodes as 00 5F, whose low byte
is 0, so it is misread as the terminator.

Fix

while (end + 1 < bytes.length && (bytes[end] !== 0 || bytes[end + 1] !== 0)) end += 2

Verification

function readUtf16(bytes) {
  let end = 0
  while (end + 1 < bytes.length && (bytes[end] !== 0 || bytes[end + 1] !== 0)) end += 2
  return bytes.toString('utf16le', 0, end)
}
const path = 'D:\\视频播放\\海康开放平台'
const bytes = Buffer.concat([Buffer.from(path, 'utf16le'), Buffer.from([0, 0])])
console.log(readUtf16(bytes)) // => D:\视频播放\海康开放平台