fix: Cyrillic window titles garbled in device list

PowerShell on Russian Windows outputs text in CP1251/CP866 by default.
Node.js reads stdout as UTF-8 → Cyrillic becomes mojibake.

Fix: force UTF-8 output at the start of every PowerShell command:
  [Console]::OutputEncoding = [System.Text.Encoding]::UTF8;
  $OutputEncoding = [System.Text.Encoding]::UTF8;

Receive stdout as raw Buffer (encoding:'buffer'), strip UTF-8 BOM
if present, then decode explicitly with .toString('utf8').

Also fixed runCommand() to collect chunks into Buffer arrays and
decode as UTF-8 (FFmpeg always outputs UTF-8 regardless of locale).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

electron/devices.js

@@ -22,21 +22,31 @@ function getFfmpegPath() {
 function runCommand(cmd, args, timeoutMs = 10000) {
   return new Promise((resolve) => {
     const proc = spawn(cmd, args, { stdio: ['pipe', 'pipe', 'pipe'] })
-    let stdout = '', stderr = ''
-    proc.stdout.on('data', d => stdout += d)
-    proc.stderr.on('data', d => stderr += d)
-    proc.on('close', () => resolve({ stdout, stderr }))
+    const outBufs = [], errBufs = []
+    proc.stdout.on('data', d => outBufs.push(d))
+    proc.stderr.on('data', d => errBufs.push(d))
+    const finish = () => {
+      // FFmpeg outputs UTF-8; on Russian Windows system tools may use CP1251,
+      // but FFmpeg is always UTF-8 — safe to decode as utf8 here.
+      const stdout = Buffer.concat(outBufs).toString('utf8')
+      const stderr = Buffer.concat(errBufs).toString('utf8')
+      resolve({ stdout, stderr })
+    }
+    proc.on('close', finish)
     proc.on('error', () => resolve({ stdout: '', stderr: '' }))
-    setTimeout(() => { try { proc.kill() } catch {} ; resolve({ stdout, stderr }) }, timeoutMs)
+    setTimeout(() => { try { proc.kill() } catch {} }, timeoutMs)
   })
 }
 
 // ─── Windows — enumerate application windows via PowerShell ───────────────────
-// Uses execFile to pass arguments as array → no quoting/escaping issues
+// KEY: force UTF-8 output BEFORE any text is written, receive as Buffer,
+// then decode as UTF-8 — this fixes Cyrillic/Unicode window titles on Russian Windows.
 function getWindowsWindowsList() {
   return new Promise((resolve) => {
-    // Each line: "WindowTitle|||ProcessName"
+    // Force UTF-8 console output so Node receives proper Unicode
     const ps1 = [
+      '[Console]::OutputEncoding = [System.Text.Encoding]::UTF8;',
+      '$OutputEncoding = [System.Text.Encoding]::UTF8;',
       'Get-Process',
       '| Where-Object { $_.MainWindowTitle -ne "" }',
       '| Sort-Object MainWindowTitle',
@@ -46,9 +56,17 @@ function getWindowsWindowsList() {
     execFile(
       'powershell.exe',
       ['-NonInteractive', '-NoProfile', '-WindowStyle', 'Hidden', '-Command', ps1],
-      { timeout: 8000, windowsHide: true },
-      (err, stdout) => {
-        if (err || !stdout) { resolve([]); return }
+      // encoding: 'buffer' — receive raw bytes, we decode manually as UTF-8
+      { timeout: 8000, windowsHide: true, encoding: 'buffer' },
+      (err, stdoutBuf) => {
+        if (err || !stdoutBuf || !stdoutBuf.length) { resolve([]); return }
+
+        // Decode the buffer as UTF-8 (PowerShell wrote UTF-8 BOM-less)
+        // Strip UTF-8 BOM if present (EF BB BF)
+        let buf = stdoutBuf
+        if (buf[0] === 0xEF && buf[1] === 0xBB && buf[2] === 0xBF) buf = buf.slice(3)
+        const stdout = buf.toString('utf8')
+
         const wins = stdout.trim().split('\n')
           .map(l => l.trim().replace(/\r$/, ''))
           .filter(Boolean)