fix: apply default HTTP2 body limit

transport/http2/server.go

@@ -209,15 +209,17 @@ func (s *Server) Serve(ctx context.Context, listener net.Listener) error {
 	}
 	s.mu.Unlock()
 
+	maxBodyBytes := s.MaxBodyBytes
+	if maxBodyBytes <= 0 {
+		maxBodyBytes = defaultMaxBodyBytes
+	}
 	requestHandler := http.Handler(http.HandlerFunc(func(writer http.ResponseWriter, request *http.Request) {
-		if s.MaxBodyBytes > 0 {
-			if request.ContentLength > s.MaxBodyBytes {
-				_ = request.Body.Close()
-				http.Error(writer, "request body too large\n", http.StatusRequestEntityTooLarge)
-				return
-			}
-			request.Body = http.MaxBytesReader(writer, request.Body, s.MaxBodyBytes)
+		if request.ContentLength > maxBodyBytes {
+			_ = request.Body.Close()
+			http.Error(writer, "request body too large\n", http.StatusRequestEntityTooLarge)
+			return
 		}
+		request.Body = http.MaxBytesReader(writer, request.Body, maxBodyBytes)
 		s.handler.ServeHTTP(writer, request)
 	}))
 	gate := &requestGate{server: s, next: requestHandler, slots: s.requestSlots}