Add miss proto

Note: this is an old proto not 3.4 so it doesn't necessarily work, then in 3.5 the music event changes so maybe it's removed in the future and includes the fireworks function?

proto/FireworkSetRsp.proto

@@ -0,0 +1,11 @@
+// Proto has been converted from Sorapointa to Grasscutter format
+syntax = "proto3";
+
+option java_package = "emu.grasscutter.net.proto";
+
+// CmdId: 5969
+// EnetChannelId: 0
+// EnetIsReliable: true
+message NBFJOJPCCEK_Rsp {
+	int32 retcode = 7;
+}