- listener/http3: default enableDatagrams to true when not explicitly set,
so CONNECT-UDP (RFC 9298) works out of the box without requiring
?enableDatagrams=true in the config URL
- handler/masque: dial target before sending 200 OK in handleConnectUDP,
matching the handleConnectTCP order; if target dial fails, the handler
can still return an error status instead of having already committed 200
- handler/masque: add missing WriteHeader(BadRequest) when ResolveUDPAddr
fails, so the client gets a proper HTTP error instead of an opaque
H3_REQUEST_CANCELLED stream reset
Fixes#103
ginuerzh
1d34d4543a