Collects the work merged for this release:

  - builds against stock httpd 2.4.52+ as well as trunk, through an
    in-tree response-compat layer, with the MPM connection-count
    notifications now optional rather than required
  - rejects a malformed HTTP/3 request with a stream error instead of
    tearing down the whole connection
  - enforces H3IdleTimeout itself, since the QUIC stacks keepalive-ping
    around the transport-level timeout
  - reads queued datagrams with recvmmsg() and stops asking the kernel
    for the local address once per datagram; adds H3SocketBufferSize
  - adds H3SessionTickets and H3EarlyData, the latter gated on an engine
    capability because OpenSSL's QUIC stack has no server-side 0-RTT
  - publishes the mod_ssl SSL_* environment for HTTP/3 requests

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>