fix: 添加数据库并发限制，解决SqlSugar连接状态冲突

AssetManager.Infrastructure/Services/MarketDataService.cs

@@ -21,6 +21,9 @@ public class MarketDataService : IMarketDataService
     private readonly IOkxMarketService _okxService;
     private readonly IMarketDataRepository _marketDataRepo;
     
+    // 限制数据库并发访问，避免 SqlSugar 连接状态冲突
+    private static readonly SemaphoreSlim _dbSemaphore = new(3, 3);
+
     public MarketDataService(
         ILogger<MarketDataService> logger,
         ITencentMarketService tencentService,
@@ -44,6 +47,10 @@ public class MarketDataService : IMarketDataService
     {
         _logger.LogInformation("获取实时价格: {Symbol}, 资产类型: {AssetType}", symbol, assetType);
         
+        // 限制数据库并发访问
+        await _dbSemaphore.WaitAsync();
+        try
+        {
             // 先查缓存
             var cached = await _marketDataRepo.GetPriceCacheAsync(symbol, assetType);
         
@@ -59,6 +66,11 @@ public class MarketDataService : IMarketDataService
                     AssetType = cached.AssetType
                 };
             }
+        }
+        finally
+        {
+            _dbSemaphore.Release();
+        }
 
         // 缓存未命中，调用API
         MarketPriceResponse response;
@@ -108,8 +120,17 @@ public class MarketDataService : IMarketDataService
         _logger.LogInformation("获取历史数据: {Symbol}, 资产类型: {AssetType}, 周期: {Timeframe}, 数量: {Limit}", 
             symbol, assetType, timeframe, limit);
         
-        // 先查缓存
+        // 限制数据库并发访问
-        var cachedKlines = await _marketDataRepo.GetKlineCacheAsync(symbol, assetType, timeframe, limit);
+        await _dbSemaphore.WaitAsync();
+        List<MarketKlineCache> cachedKlines;
+        try
+        {
+            cachedKlines = await _marketDataRepo.GetKlineCacheAsync(symbol, assetType, timeframe, limit);
+        }
+        finally
+        {
+            _dbSemaphore.Release();
+        }
         
         // 缓存足够，直接返回
         if (cachedKlines.Count >= limit)
@@ -214,7 +235,15 @@ public class MarketDataService : IMarketDataService
             ExpiredAt = GetCacheExpirationTime(assetType)
         };
 
+        await _dbSemaphore.WaitAsync();
+        try
+        {
             await _marketDataRepo.SavePriceCacheAsync(cacheEntity);
+        }
+        finally
+        {
+            _dbSemaphore.Release();
+        }
         _logger.LogDebug("缓存写入: {Symbol} {AssetType}, 过期时间: {ExpiredAt}", symbol, assetType, cacheEntity.ExpiredAt);
     }
 
@@ -235,7 +264,15 @@ public class MarketDataService : IMarketDataService
             FetchedAt = DateTime.Now
         }).ToList();
 
+        await _dbSemaphore.WaitAsync();
+        try
+        {
             await _marketDataRepo.SaveKlineCacheBatchAsync(cacheEntities);
+        }
+        finally
+        {
+            _dbSemaphore.Release();
+        }
         _logger.LogDebug("历史K线缓存写入: {Symbol} {AssetType} {Timeframe}, 数量: {Count}", symbol, assetType, timeframe, cacheEntities.Count);
     }