Merge feat/http-dispatcher-transport-abstraction: Expose EventEnvelope-level dispatch API for non-QUIC transports
Cross-crate change (alknet-call): expose Dispatcher::dispatch_requested as pub,
extract abort-cascade handling into pub handle_abort method, add
CallConnection::new_overlay_only(identity) constructor (Option A) for non-QUIC
transports. Existing QUIC path (CallAdapter, CallClient, run_loop, handle_stream)
unchanged. 13 unit tests in alknet-call + 6 integration tests in alknet-http.
glm-5.2
9512e61e73