- Introduce `isTransientTransportError` to identify transient transport errors such as TLS handshake, DNS, and connection resets.
- Extend retry logic to handle these errors without enforcing credential cooldown.
- Add new constants, such as `ErrorCodeTransientTransport`, to categorize and manage these errors.
- Refactor `conductor_selection` to distinguish request-retry round errors.
- Add comprehensive tests covering transport retries, cooldown behavior, and transient error handling.
Closes: #5829