多轮审查和修复

Assets/Scripts/Support/Platform/NullPlatformService.cs

@@ -0,0 +1,46 @@
+using System.Threading.Tasks;
+using UnityEngine;
+
+namespace BaseGames.Platform
+{
+    /// <summary>
+    /// IPlatformService 的空实现，无平台 SDK 时作为默认服务使用。
+    /// 所有操作均为无操作（no-op）或返回安全默认值。
+    /// </summary>
+    public class NullPlatformService : IPlatformService
+    {
+        public bool IsInitialized   => true;
+        public bool IsCloudAvailable => false;
+
+        public Task<bool> InitializeAsync() => Task.FromResult(true);
+        public void RunCallbacks()          { }
+        public void Shutdown()              { }
+
+        public void UnlockAchievement(string achievementId)
+            => Debug.Log($"[NullPlatform] UnlockAchievement: {achievementId}");
+
+        public void ClearAchievement(string achievementId) { }
+
+        public Task<bool> IsAchievementUnlocked(string achievementId)
+            => Task.FromResult(false);
+
+        public void SetStat(string statId, int value)           { }
+        public void IncrementStat(string statId, int increment = 1) { }
+        public int  GetStat(string statId)                      => 0;
+
+        public Task<bool>   CloudSaveAsync(string fileName, byte[] data) => Task.FromResult(false);
+        public Task<byte[]> CloudLoadAsync(string fileName)               => Task.FromResult<byte[]>(null);
+
+        public void SetRichPresence(string key, string value)   { }
+        public void ClearRichPresence()                         { }
+
+        public void SubmitLeaderboardScore(string boardId, long score)
+            => Debug.Log($"[NullPlatform] SubmitLeaderboardScore: {boardId} = {score}");
+
+        public Task<LeaderboardEntry[]> GetLeaderboardEntries(string boardId, int maxCount)
+            => Task.FromResult(System.Array.Empty<LeaderboardEntry>());
+
+        public bool IsDLCOwned(string dlcId)    => false;
+        public void ShowOverlay(string dialog)  { }
+    }
+}