fix(voice): start codex login without the server's provider secrets

The login child inherited the whole server environment, including
OPENAI_API_KEY and every other provider credential. Pass only what Codex
needs to find its home, open a browser and reach OpenAI through a proxy.

server/providers/openai/codex-auth.js

@@ -138,6 +138,21 @@ export function resolveCodexExecutable({
   return 'codex';
 }
 
+// What `codex login` needs to find its home, open a browser and reach OpenAI.
+// The server's own environment also holds every provider secret, so the
+// child receives only these names.
+const CODEX_LOGIN_ENV =
+  /^(?:PATH|PATHEXT|HOME|USER|USERNAME|LOGNAME|SHELL|LANG|LANGUAGE|LC_[A-Z_]+|TERM|TZ|TMPDIR|TEMP|TMP|XDG_[A-Z_]+|DISPLAY|WAYLAND_DISPLAY|DBUS_SESSION_BUS_ADDRESS|BROWSER|WSL_[A-Z_]+|WSLENV|(?:HTTPS?|ALL|NO)_PROXY|SSL_CERT_(?:FILE|DIR)|NODE_EXTRA_CA_CERTS|SYSTEMROOT|WINDIR|COMSPEC|USERPROFILE|APPDATA|LOCALAPPDATA|PROGRAMDATA|HOMEDRIVE|HOMEPATH|CODEX_[A-Z_]+)$/i;
+
+/** The environment `codex login` runs with: the allowlist, then `CODEX_HOME`. */
+export function codexLoginEnvironment(environment, codexHome) {
+  const env = {};
+  for (const [name, value] of Object.entries(environment || {}))
+    if (CODEX_LOGIN_ENV.test(name) && value !== undefined) env[name] = value;
+  env.CODEX_HOME = codexHome;
+  return env;
+}
+
 export function startCodexChatGptLogin({
   spawnImpl = spawn,
   environment = process.env,
@@ -182,7 +197,7 @@ export function startCodexChatGptLogin({
         cwd: home,
         detached: true,
         stdio: 'ignore',
-        env: { ...environment, CODEX_HOME: loginHome },
+        env: codexLoginEnvironment(environment, loginHome),
       });
     } catch {
       fail();

src/codexOauthRealtime.test.mjs

@@ -168,7 +168,13 @@ test('Codex login resolves an installed executable before PATH and starts browse
   const pending = startCodexChatGptLogin({
     executable: '/fixture/codex',
     home: '/home/fixture',
-    environment: { PATH: '/fixture' },
+    environment: {
+      PATH: '/fixture',
+      https_proxy: 'http://proxy.fixture:8080',
+      OPENAI_API_KEY: 'fixture-api-key',
+      GOOGLE_MAPS_SERVER_API_KEY: 'fixture-google-key',
+      OPENSKY_CLIENT_SECRET: 'fixture-opensky-secret',
+    },
     spawnImpl(command, args, options) {
       calls.push({ command, args, options });
       queueMicrotask(() => child.emit('spawn'));
@@ -181,9 +187,14 @@ test('Codex login resolves an installed executable before PATH and starts browse
   assert.deepEqual(calls[0].args, ['login']);
   assert.equal(calls[0].options.detached, true);
   assert.equal(calls[0].options.stdio, 'ignore');
-  assert.equal(
-    calls[0].options.env.CODEX_HOME,
-    path.join('/home/fixture', '.codex'),
+  assert.deepEqual(
+    calls[0].options.env,
+    {
+      PATH: '/fixture',
+      https_proxy: 'http://proxy.fixture:8080',
+      CODEX_HOME: path.join('/home/fixture', '.codex'),
+    },
+    'provider secrets stay out of the login process',
   );
   child.emit('exit', 1);
   assert.deepEqual(await login.completion, { exitCode: 1 });