Fixed null pointer exception in game only mode

PacketPlayerLoginRsp now creates the required QuerryCurrRegionHttpRsp itself.

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

 package emu.grasscutter.server.packet.send;
 
+import com.google.protobuf.ByteString;
 import emu.grasscutter.Grasscutter;
 import emu.grasscutter.net.packet.GenshinPacket;
 import emu.grasscutter.net.packet.PacketOpcodes;
 import emu.grasscutter.net.proto.PlayerLoginRspOuterClass.PlayerLoginRsp;
+import emu.grasscutter.net.proto.QueryCurrRegionHttpRspOuterClass;
 import emu.grasscutter.net.proto.RegionInfoOuterClass.RegionInfo;
 import emu.grasscutter.server.game.GameSession;
+import emu.grasscutter.utils.FileUtils;
+
+import java.io.File;
+import java.net.URL;
+import java.util.Base64;
 
 public class PacketPlayerLoginRsp extends GenshinPacket {
 
+	private static QueryCurrRegionHttpRspOuterClass.QueryCurrRegionHttpRsp regionCache;
+
 	public PacketPlayerLoginRsp(GameSession session) {
 		super(PacketOpcodes.PlayerLoginRsp, 1);
 		
 		this.setUseDispatchKey(true);
 
-		RegionInfo info = Grasscutter.getDispatchServer().getCurrRegion().getRegionInfo();
+		RegionInfo info;
+
+		if(Grasscutter.getConfig().RunMode.equalsIgnoreCase("GAME_ONLY")) {
+			if (regionCache == null) {
+				try {
+					File file = new File(Grasscutter.getConfig().DATA_FOLDER + "query_cur_region.txt");
+					String query_cur_region = "";
+					if (file.exists()) {
+						query_cur_region = new String(FileUtils.read(file));
+					} else {
+						Grasscutter.getLogger().warn("query_cur_region not found! Using default current region.");
+					}
+
+					byte[] decodedCurRegion = Base64.getDecoder().decode(query_cur_region);
+					QueryCurrRegionHttpRspOuterClass.QueryCurrRegionHttpRsp regionQuery = QueryCurrRegionHttpRspOuterClass.QueryCurrRegionHttpRsp.parseFrom(decodedCurRegion);
+
+					RegionInfo serverRegion = regionQuery.getRegionInfo().toBuilder()
+							.setIp((Grasscutter.getConfig().getGameServerOptions().PublicIp.isEmpty() ? Grasscutter.getConfig().getGameServerOptions().Ip : Grasscutter.getConfig().getGameServerOptions().PublicIp))
+							.setPort(Grasscutter.getConfig().getGameServerOptions().Port)
+							.setSecretKey(ByteString.copyFrom(FileUtils.read(Grasscutter.getConfig().KEY_FOLDER + "dispatchSeed.bin")))
+							.build();
+
+					regionCache = regionQuery.toBuilder().setRegionInfo(serverRegion).build();
+				} catch (Exception e) {
+					Grasscutter.getLogger().error("Error while initializing region cache!", e);
+				}
+			}
+
+			info = regionCache.getRegionInfo();
+		} else {
+			info = Grasscutter.getDispatchServer().getCurrRegion().getRegionInfo();
+		}
 
 		PlayerLoginRsp p = PlayerLoginRsp.newBuilder()
 				.setIsUseAbilityHash(true) // true