Added a lightweight, zero-dependency event bus to the `AuthSdk` to listen for Valkey RESP3 push invalidation events and emit them to registered listeners.
The implementation properly captures errors from synchronous and asynchronous listeners, ensuring they do not crash the primary SDK listener loop. Extracted the Valkey event processor to improve hermetic testability.
Co-authored-by: mrteye <1945243+mrteye@users.noreply.github.com>
