fix: 크로스 프로젝트 통신 버그 수정

- Tokens 타입 string? → Dictionary<string,string>? (Go API JSON object 역직렬화 실패 수정)
- 409 응답 핸들러 return false → return null (컴파일 에러 수정)
- INTO_BOSS_RAID 파티원 각자에게 본인 토큰과 함께 전달 (기존: 파티장에게 N번 중복)
- GetPlayer null 체크 추가 (NullReferenceException 방지)
- BossId 하드코딩 1 → packet.RaidId 사용
- Player 클래스에 Experience/AttackPower 등 전투 스탯 필드 추가
- ToPlayerInfo에서 새 필드 매핑 추가
- OnIntoChannelParty Nickname을 Session.UserName에서 가져오도록 수정

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

MMOTestServer/MMOserver/Game/GameServer.cs

@@ -406,7 +406,12 @@ public class GameServer : ServerBase
             Mp = player.Mp,
             MaxMp = player.MaxMp,
             Position = new Position { X = player.PosX, Y = player.PosY, Z = player.PosZ },
-            RotY = player.RotY
+            RotY = player.RotY,
+            Experience = player.Experience,
+            NextExp = player.NextExp,
+            AttackPower = player.AttackPower,
+            AttackRange = player.AttackRange,
+            SprintMultiplier = player.SprintMultiplier
         };
     }
 
@@ -574,12 +579,17 @@ public class GameServer : ServerBase
 
             if (memberPeer != null)
             {
+                // 세션에서 username 조회
+                string nickname = memberPeer.Tag is Session s && !string.IsNullOrEmpty(s.UserName)
+                    ? s.UserName
+                    : memberId.ToString();
+
                 // 새 채널에 유저 추가
                 Player newPlayer = new()
                 {
                     HashKey = memberId,
                     PlayerId = memberId,
-                    Nickname = memberId.ToString()
+                    Nickname = nickname
                 };
                 cm.AddUser(packet.ChannelId, memberId, newPlayer, memberPeer);
 
@@ -1073,10 +1083,16 @@ public class GameServer : ServerBase
         List<string> userNames = new List<string>();
         foreach (int memberId in party.PartyMemberIds)
         {
-            userNames.Add(channel.GetPlayer(memberId).Nickname);
+            Player? member = channel.GetPlayer(memberId);
+            if (member == null)
+            {
+                continue;
+            }
+
+            userNames.Add(member.Nickname);
         }
 
-        BossRaidResult? result = await RestApi.Instance.BossRaidAccesssAsync(userNames, 1);
+        BossRaidResult? result = await RestApi.Instance.BossRaidAccesssAsync(userNames, packet.RaidId);
 
         // 입장 실패
         if (result == null || result.BossId <= 0)
@@ -1143,11 +1159,13 @@ public class GameServer : ServerBase
 
             SendTo(memberPeer, PacketSerializer.Serialize((ushort)PacketCode.CHANGE_MAP, response));
 
-            // 모두에게 레이드로 이동 (할당된 실제 레이드 맵 ID 전달)
-            SendTo(peer,
+            // 각 파티원에게 레이드 입장 정보 전달 (본인의 토큰 포함)
+            string? memberToken = null;
+            result.Tokens?.TryGetValue(memberPlayer.Nickname, out memberToken);
+            SendTo(memberPeer,
                 PacketSerializer.Serialize((ushort)PacketCode.INTO_BOSS_RAID,
                     new IntoBossRaidPacket
-                        { RaidId = assignedRaidMapId, IsSuccess = true, Session = result.SessionName, Token = result.Tokens }));
+                        { RaidId = assignedRaidMapId, IsSuccess = true, Session = result.SessionName, Token = memberToken }));
         }
 
         Log.Debug("[GameServer] INTO_BOSS_RAID HashKey={Key} PartyId={PartyId} AssignedRaidMapId={RaidId}", hashKey, party.PartyId,