add: sign in with chatgpt (#963)

Sign in with ChatGPT to get an API key (flow to grant API credits for Plus/Pro coming later today!)

codex-cli/package.json

@@ -31,6 +31,7 @@
     "chalk": "^5.2.0",
     "diff": "^7.0.0",
     "dotenv": "^16.1.4",
+    "express": "^5.1.0",
     "fast-deep-equal": "^3.1.3",
     "fast-npm-meta": "^0.4.2",
     "figures": "^6.1.0",
@@ -54,6 +55,7 @@
   "devDependencies": {
     "@eslint/js": "^9.22.0",
     "@types/diff": "^7.0.2",
+    "@types/express": "^5.0.1",
     "@types/js-yaml": "^4.0.9",
     "@types/marked-terminal": "^6.1.1",
     "@types/react": "^18.0.32",