fix: 复用YahooQuotes实例，添加并发限制防止429错误

AssetManager.Infrastructure/Services/YahooMarketService.cs

@@ -25,14 +25,23 @@ public interface IYahooMarketService
 }
 /// <summary>
 /// Yahoo财经市场数据服务实现
+/// <para>⚠️ Yahoo API 有频率限制，频繁请求会触发 429 错误</para>
+/// <para>建议：依赖缓存机制减少 API 调用</para>
 /// </summary>
 public class YahooMarketService : IYahooMarketService
 {
     private readonly ILogger<YahooMarketService> _logger;
+    private readonly YahooQuotes _yahooQuotes;
+    private readonly SemaphoreSlim _semaphore = new(1, 1); // 限制并发请求
 
     public YahooMarketService(ILogger<YahooMarketService> logger)
     {
         _logger = logger;
+        // 复用单个实例，设置足够长的历史范围（2年）
+        // YahooQuotes 内部会缓存 cookie/crumb，避免频繁请求
+        _yahooQuotes = new YahooQuotesBuilder()
+            .WithHistoryStartDate(Instant.FromDateTimeUtc(DateTime.UtcNow.AddDays(-730)))
+            .Build();
     }
 
     /// <summary>
@@ -50,34 +59,16 @@ public class YahooMarketService : IYahooMarketService
         return symbol.ToUpper().Replace(".", "-");
     }
 
-    /// <summary>
-    /// 根据 timeframe 和 limit 计算需要的开始日期
-    /// </summary>
-    private DateTime CalculateStartDate(string timeframe, int limit)
-    {
-        var now = DateTime.UtcNow;
-        
-        // 根据周期类型计算需要的天数，预留缓冲
-        return timeframe.ToLower() switch
-        {
-            "1d" or "daily" or "day" => now.AddDays(-limit * 1.5),       // 日线：limit * 1.5 天
-            "1w" or "weekly" or "week" => now.AddDays(-limit * 8),       // 周线：limit * 8 天
-            "1m" or "monthly" or "month" => now.AddDays(-limit * 35),    // 月线：limit * 35 天
-            _ => now.AddDays(-Math.Max(limit * 2, 365))                  // 默认：至少365天
-        };
-    }
-
     public async Task<MarketPriceResponse> GetStockPriceAsync(string symbol)
     {
         var yahooSymbol = ConvertToYahooSymbol(symbol);
         _logger.LogInformation("Yahoo获取股票价格: {Symbol} -> {YahooSymbol}", symbol, yahooSymbol);
         
-        // 实时价格不需要历史数据，使用最小范围
+        // 限制并发，避免触发 429
-        var yahooQuotes = new YahooQuotesBuilder()
+        await _semaphore.WaitAsync();
-            .WithHistoryStartDate(Instant.FromDateTimeUtc(DateTime.UtcNow.AddDays(-7)))
+        try
-            .Build();
+        {
-        
+            Snapshot? snapshot = await _yahooQuotes.GetSnapshotAsync(yahooSymbol);
-        Snapshot? snapshot = await yahooQuotes.GetSnapshotAsync(yahooSymbol);
             if (snapshot is null)
                 throw new InvalidOperationException($"Yahoo未知标的: {symbol}");
             
@@ -94,28 +85,29 @@ public class YahooMarketService : IYahooMarketService
 
             return new MarketPriceResponse
             {
-            Symbol = symbol, // 返回原始代码
+                Symbol = symbol,
                 Price = price,
                 PreviousClose = previousClose,
                 Timestamp = DateTime.UtcNow,
                 AssetType = "Stock"
             };
         }
+        finally
+        {
+            _semaphore.Release();
+        }
+    }
 
     public async Task<List<MarketDataResponse>> GetStockHistoricalDataAsync(string symbol, string timeframe, int limit)
     {
         var yahooSymbol = ConvertToYahooSymbol(symbol);
         _logger.LogInformation("Yahoo获取历史数据: {Symbol} -> {YahooSymbol}, {Timeframe}, {Limit}", symbol, yahooSymbol, timeframe, limit);
         
-        // 根据请求参数动态计算开始日期
+        // 限制并发，避免触发 429
-        var startDate = CalculateStartDate(timeframe, limit);
+        await _semaphore.WaitAsync();
-        _logger.LogDebug("历史数据开始日期: {StartDate}", startDate.ToString("yyyy-MM-dd"));
+        try
-        
+        {
-        var yahooQuotes = new YahooQuotesBuilder()
+            Result<History> result = await _yahooQuotes.GetHistoryAsync(yahooSymbol);
-            .WithHistoryStartDate(Instant.FromDateTimeUtc(startDate))
-            .Build();
-        
-        Result<History> result = await yahooQuotes.GetHistoryAsync(yahooSymbol);
             if (result.Value == null)
                 throw new InvalidOperationException($"Yahoo获取历史数据失败，标的: {symbol}");
             
@@ -128,7 +120,7 @@ public class YahooMarketService : IYahooMarketService
             {
                 marketDataList.Add(new MarketDataResponse
                 {
-                Symbol = symbol, // 返回原始代码
+                    Symbol = symbol,
                     Timestamp = tick.Date.ToDateTimeUtc(),
                     Open = (decimal)tick.Open,
                     High = (decimal)tick.High,
@@ -149,4 +141,9 @@ public class YahooMarketService : IYahooMarketService
             
             return sortedData;
         }
+        finally
+        {
+            _semaphore.Release();
+        }
+    }
 }