- Fix Claude, Codex, and Cursor auth handlers to check if CLI is already authenticated
- Use same detection logic as each provider's internal checkAuth/codexAuthIndicators()
- For Codex: Check for API keys and auth files before requiring manual login
- For Cursor: Check for env var and credentials files before requiring manual auth
- For Claude: Check for cached auth tokens, settings, and credentials files
- If CLI is already authenticated: Just reconnect by removing disconnected marker
- If CLI needs auth: Tell user to manually run login command
- This prevents timeout errors when login commands can't run in non-interactive mode
