## Why
ChatGPT credentials can rotate while a remote executor is idle. Registry requests need to follow stored rotations without continuing after logout or switching the executor's identity. Concurrent refreshes must also avoid overwriting newer credentials.
## What changed
- Reload and validate ChatGPT credentials before registry requests, pinning the credential mode, account, user, and workspace policy. Reuse cached metadata for unchanged personal access tokens.
- Retry registration when temporary credential resolution failures prevent a request from being sent. Bound credential resolution and block reuse of a token generation whose refresh outcome is unknown.
- Restrict supported authentication modes before executor startup loads credentials or cloud configuration.
- Serialize persistent credential writes across cooperating processes and compare stored credentials before committing refreshed tokens.
- Replace `auth.json` atomically so overlapping readers see a complete document, preserving symlink targets and protecting file permissions, including Windows access controls.
## Testing
Add coverage for credential rotation, logout, identity changes, cancelled refresh callers, temporary metadata failures, registration retries, concurrent credential writes, and atomic file replacement.
GitOrigin-RevId: 6b210944bf8eba2f45bc27113f901d2c3cb06b48
## What changed
Extract executor startup into `codex-exec-server-cli`, shared by `codex exec-server` and the new standalone binary. Preserve executor arguments, authentication, configuration overrides, and sandbox helper dispatch across both entry points.
Build the standalone binary with `cargo build -p codex-exec-server-cli --bin codex-exec-server` and run it with `codex-exec-server --listen stdio`.
## Testing
Add standalone CLI parsing and help coverage, plus an integration test for version reporting, stdio initialization, filesystem reads, process execution, and sandbox helper re-execution when supported.
GitOrigin-RevId: ab3a81c6b91b6f45e4d72d8add2e01af8372e97f