fix SetPlayerBirthdayRsp

src/main/java/emu/grasscutter/server/packet/recv/HandlerSetPlayerBirthdayReq.java

 package emu.grasscutter.server.packet.recv;
 
-import emu.grasscutter.server.game.GameSession;
-import emu.grasscutter.server.packet.send.PacketGetPlayerSocialDetailRsp;
-import emu.grasscutter.server.packet.send.PacketSetPlayerBirthdayRsp;
-
 import emu.grasscutter.net.packet.Opcodes;
-import emu.grasscutter.net.packet.PacketOpcodes;
 import emu.grasscutter.net.packet.PacketHandler;
-
-import emu.grasscutter.net.proto.SocialDetailOuterClass.SocialDetail;
+import emu.grasscutter.net.packet.PacketOpcodes;
 import emu.grasscutter.net.proto.SetPlayerBirthdayReqOuterClass.SetPlayerBirthdayReq;
-
-import com.google.gson.Gson;
+import emu.grasscutter.net.proto.SocialDetailOuterClass.SocialDetail;
+import emu.grasscutter.server.game.GameSession;
+import emu.grasscutter.server.packet.send.PacketGetPlayerSocialDetailRsp;
+import emu.grasscutter.server.packet.send.PacketSetPlayerBirthdayRsp;
 
 @Opcodes(PacketOpcodes.SetPlayerBirthdayReq)
 public class HandlerSetPlayerBirthdayReq extends PacketHandler {
@@ -19,10 +15,9 @@ public class HandlerSetPlayerBirthdayReq extends PacketHandler {
     public void handle(GameSession session, byte[] header, byte[] payload) throws Exception {
         SetPlayerBirthdayReq req = SetPlayerBirthdayReq.parseFrom(payload);
 
-		if(req.getBirth() != null && req.getBirth().getDay() > 0 && req.getBirth().getMonth() > 0)
-		{
-			int day = req.getBirth().getDay();
-			int month = req.getBirth().getMonth();
+        if (req.getBirthday().getDay() > 0 && req.getBirthday().getMonth() > 0) {
+            int day = req.getBirthday().getDay();
+            int month = req.getBirthday().getMonth();
 
             // Update birthday value
             session.getPlayer().setBirthday(day, month);

src/main/java/emu/grasscutter/server/packet/send/PacketSetPlayerBirthdayRsp.java

 package emu.grasscutter.server.packet.send;
 
-import emu.grasscutter.Grasscutter;
 import emu.grasscutter.game.GenshinPlayer;
 import emu.grasscutter.net.packet.GenshinPacket;
 import emu.grasscutter.net.packet.PacketOpcodes;
 import emu.grasscutter.net.proto.SetPlayerBirthdayRspOuterClass.SetPlayerBirthdayRsp;
-import emu.grasscutter.net.proto.BirthdayOuterClass.Birthday;
 
 public class PacketSetPlayerBirthdayRsp extends GenshinPacket {
     public PacketSetPlayerBirthdayRsp(GenshinPlayer player) {
         super(PacketOpcodes.SetPlayerBirthdayRsp);
 
         SetPlayerBirthdayRsp proto = SetPlayerBirthdayRsp.newBuilder()
-                .setBirth(player.getBirthday().toProto())
+                .setBirthday(player.getBirthday().toProto())
                 .build();
 
         this.setData(proto);