Even faster connection establishment with QUIC 0-RTT resumption

The latest revision of the TLS protocol, TLS 1.3, introduced "zero roundtrip time connection resumption" (0-RTT), which allows clients to start sending application data without waiting for the TLS handshake to complete, reducing latency. QUIC goes a step further by allowing clients to send application data in the first roundtrip of the connection. However, 0-RTT connection resumption comes with risks such as lack of forward secrecy and potential replay attacks on non-idempotent requests. Cloudflare supports 0-RTT resumption for QUIC and offers a toggle to control whether it is enabled or not in the Cloudflare dashboard.