fix(desktop): Harden local file tree paths

apps/desktop/electron/fs-read-dir.cjs

@@ -0,0 +1,109 @@
+'use strict'
+
+const fs = require('node:fs')
+const path = require('node:path')
+const { resolveDirectoryForIpc } = require('./hardening.cjs')
+
+const FS_READDIR_STAT_CONCURRENCY = 16
+
+// Always-hidden noise (covers non-git projects too; gitignore catches many of
+// these, but the project tree should keep the same hygiene without one).
+const FS_READDIR_HIDDEN = new Set([
+  '.git',
+  '.hg',
+  '.svn',
+  '.cache',
+  '.next',
+  '.turbo',
+  '.venv',
+  '__pycache__',
+  'build',
+  'dist',
+  'node_modules',
+  'target',
+  'venv'
+])
+
+function direntIsDirectory(dirent) {
+  return typeof dirent.isDirectory === 'function' && dirent.isDirectory()
+}
+
+function direntIsFile(dirent) {
+  return typeof dirent.isFile === 'function' && dirent.isFile()
+}
+
+function direntIsSymbolicLink(dirent) {
+  return typeof dirent.isSymbolicLink === 'function' && dirent.isSymbolicLink()
+}
+
+function shouldStatDirent(dirent) {
+  if (direntIsDirectory(dirent)) return false
+
+  return direntIsSymbolicLink(dirent) || !direntIsFile(dirent)
+}
+
+async function entryForDirent(dirent, resolved, fsImpl) {
+  const fullPath = path.join(resolved, dirent.name)
+  let isDirectory = direntIsDirectory(dirent)
+
+  if (!isDirectory && shouldStatDirent(dirent)) {
+    try {
+      isDirectory = (await fsImpl.promises.stat(fullPath)).isDirectory()
+    } catch {
+      isDirectory = false
+    }
+  }
+
+  return { name: dirent.name, path: fullPath, isDirectory }
+}
+
+async function mapWithStatConcurrency(items, mapper) {
+  const results = new Array(items.length)
+  let nextIndex = 0
+
+  async function runWorker() {
+    while (nextIndex < items.length) {
+      const index = nextIndex
+      nextIndex += 1
+      results[index] = await mapper(items[index])
+    }
+  }
+
+  const workerCount = Math.min(FS_READDIR_STAT_CONCURRENCY, items.length)
+  const workers = Array.from({ length: workerCount }, () => runWorker())
+  await Promise.all(workers)
+
+  return results
+}
+
+async function readDirForIpc(dirPath, options = {}) {
+  const fsImpl = options.fs || fs
+  let resolved
+
+  try {
+    ;({ resolvedPath: resolved } = await resolveDirectoryForIpc(dirPath, {
+      fs: fsImpl,
+      purpose: 'Directory read'
+    }))
+  } catch (error) {
+    return { entries: [], error: error?.code || 'read-error' }
+  }
+
+  try {
+    const dirents = await fsImpl.promises.readdir(resolved, { withFileTypes: true })
+    const visibleDirents = dirents.filter(dirent => !FS_READDIR_HIDDEN.has(dirent.name))
+    const entries = await mapWithStatConcurrency(visibleDirents, dirent =>
+      entryForDirent(dirent, resolved, fsImpl)
+    )
+
+    entries.sort((a, b) => Number(b.isDirectory) - Number(a.isDirectory) || a.name.localeCompare(b.name))
+
+    return { entries }
+  } catch (error) {
+    return { entries: [], error: error?.code || 'read-error' }
+  }
+}
+
+module.exports = {
+  readDirForIpc
+}