implement sender side behavior for RESET_STREAM_AT (#5242)

* improve existing send stream test

* implement sender side behavior for RESET_STREAM_AT

* refactor send stream cancelation and shutdown error handling

* correctly deal with 0-RTT corner case

streams_map_outgoing.go

@@ -13,6 +13,7 @@ import (
 
 type outgoingStream interface {
 	updateSendWindow(protocol.ByteCount)
+	enableResetStreamAt()
 	closeForShutdown(error)
 }
 
@@ -204,6 +205,14 @@ func (m *outgoingStreamsMap[T]) UpdateSendWindow(limit protocol.ByteCount) {
 	m.mutex.Unlock()
 }
 
+func (m *outgoingStreamsMap[T]) EnableResetStreamAt() {
+	m.mutex.Lock()
+	for _, str := range m.streams {
+		str.enableResetStreamAt()
+	}
+	m.mutex.Unlock()
+}
+
 // unblockOpenSync unblocks the next OpenStreamSync go-routine to open a new stream
 func (m *outgoingStreamsMap[T]) maybeUnblockOpenSync() {
 	if len(m.openQueue) == 0 {