Description

Add Config::max_connection_send_data to override Quinn's connection-level send window independently from max_connection_data.

This enables tuning for high BDP to improve throughput, while preserving Quinn's default TransportConfig::send_window when unset.

Notes & open questions

We've originally made this change for https://github.com/hypha-space/hypha to improve cross continental cloud-to-cloud links as defaulted to max_connection_data in case max_connection_send_data isn't set in line with what the docs say but for backward compatibility I've change this such that we fallback to Quinn's defaults. In line with that I've adjusted the docs.

Change checklist

Add Config::max_connection_send_data to override Quinn's connection-level send window independently from max_connection_data.

This enables tuning for high BDP to improve throughput, while preserving Quinn's default TransportConfig::send_window when unset.

• I have performed a self-review of my own code
• I have made corresponding changes to the documentation
• I have added tests that prove my fix is effective or that my feature works
• A changelog entry has been made in the appropriate crates