fix(responses): respect send queue limits during reconnect (#4000)

## Summary

Responses WebSocket connections now honor `max_queue_size` during
reconnect even when no messages were queued before connecting.

## Changes

- Keep the caller's configured send queue for synchronous and
asynchronous Responses connections, including beta Responses.
- Continue raising `WebSocketQueueFullError` at the configured byte
limit and flush admitted messages after reconnect.

Co-authored-by: markstuart-oai <323302876+markstuart-oai@users.noreply.github.com>