refactor: 后端架构优化 P0-P1

P0: 移除硬编码 API Key
- MarketDataService Tiingo Key 改为强制环境变量

P1: 拆分 Entity 文件
- 从 Portfolio.cs 提取 Position.cs
- 从 Portfolio.cs 提取 Transaction.cs
- 每个实体独立文件，符合单一职责原则

AssetManager.Data/Portfolio.cs

@@ -68,161 +68,3 @@ public class Portfolio
     [SugarColumn(ColumnName = "updated_at")]
     public DateTime UpdatedAt { get; set; }
 }
-
-/// <summary>
-/// 持仓明细表
-/// </summary>
-[SugarTable("positions")]
-public class Position
-{
-    /// <summary>
-    /// 主键
-    /// </summary>
-    [SugarColumn(IsPrimaryKey = true, IsIdentity = false)]
-    public string? Id { get; set; }
-    
-    /// <summary>
-    /// 所属组合ID
-    /// </summary>
-    [SugarColumn(ColumnName = "portfolio_id", IndexGroupNameList = new string[] { "idx_portfolio_id" })]
-    public string? PortfolioId { get; set; }
-    
-    /// <summary>
-    /// 标的代码 (如: UPRO.US)
-    /// </summary>
-    [SugarColumn(ColumnName = "stock_code", Length = 50)]
-    public string? StockCode { get; set; }
-    
-    /// <summary>
-    /// 标的名称
-    /// </summary>
-    [SugarColumn(ColumnName = "stock_name", Length = 200)]
-    public string? StockName { get; set; }
-    
-    /// <summary>
-    /// 资产类型 (Stock/Crypto)
-    /// </summary>
-    [SugarColumn(ColumnName = "asset_type", Length = 20)]
-    public string? AssetType { get; set; }
-    
-    /// <summary>
-    /// 持有数量
-    /// </summary>
-    [SugarColumn(ColumnName = "shares", ColumnDataType = "decimal(18,8)")]
-    public decimal Shares { get; set; }
-    
-    /// <summary>
-    /// 持仓均价
-    /// </summary>
-    [SugarColumn(ColumnName = "avg_price", ColumnDataType = "decimal(18,4)")]
-    public decimal AvgPrice { get; set; }
-    
-    /// <summary>
-    /// 标的币种
-    /// </summary>
-    [SugarColumn(ColumnName = "currency", Length = 10)]
-    public string? Currency { get; set; }
-    
-    /// <summary>
-    /// 建仓时间
-    /// </summary>
-    [SugarColumn(ColumnName = "created_at")]
-    public DateTime CreatedAt { get; set; }
-    
-    /// <summary>
-    /// 最后更新时间
-    /// </summary>
-    [SugarColumn(ColumnName = "updated_at")]
-    public DateTime UpdatedAt { get; set; }
-}
-
-/// <summary>
-/// 交易流水表
-/// </summary>
-[SugarTable("transactions")]
-public class Transaction
-{
-    /// <summary>
-    /// 主键
-    /// </summary>
-    [SugarColumn(IsPrimaryKey = true, IsIdentity = false)]
-    public string? Id { get; set; }
-    
-    /// <summary>
-    /// 所属组合ID
-    /// </summary>
-    [SugarColumn(ColumnName = "portfolio_id", IndexGroupNameList = new string[] { "idx_portfolio_id" })]
-    public string? PortfolioId { get; set; }
-    
-    /// <summary>
-    /// 交易类型 (buy/sell)
-    /// </summary>
-    [SugarColumn(ColumnName = "type", Length = 20)]
-    public string? Type { get; set; }
-    
-    /// <summary>
-    /// 标的代码
-    /// </summary>
-    [SugarColumn(ColumnName = "stock_code", Length = 50)]
-    public string? StockCode { get; set; }
-    
-    /// <summary>
-    /// 资产类型 (Stock/Crypto)
-    /// </summary>
-    [SugarColumn(ColumnName = "asset_type", Length = 20)]
-    public string? AssetType { get; set; }
-    
-    /// <summary>
-    /// 交易标题 (如: 定期定投)
-    /// </summary>
-    [SugarColumn(ColumnName = "title", Length = 200)]
-    public string? Title { get; set; }
-    
-    /// <summary>
-    /// 交易数量
-    /// </summary>
-    [SugarColumn(ColumnName = "amount", ColumnDataType = "decimal(18,8)")]
-    public decimal Amount { get; set; }
-    
-    /// <summary>
-    /// 成交价格
-    /// </summary>
-    [SugarColumn(ColumnName = "price", ColumnDataType = "decimal(18,4)")]
-    public decimal Price { get; set; }
-    
-    /// <summary>
-    /// 交易总金额
-    /// </summary>
-    [SugarColumn(ColumnName = "total_amount", ColumnDataType = "decimal(18,4)")]
-    public decimal TotalAmount { get; set; }
-    
-    /// <summary>
-    /// 交易币种
-    /// </summary>
-    [SugarColumn(ColumnName = "currency", Length = 10)]
-    public string? Currency { get; set; }
-    
-    /// <summary>
-    /// 交易状态 (processing/completed)
-    /// </summary>
-    [SugarColumn(ColumnName = "status", Length = 50)]
-    public string? Status { get; set; }
-    
-    /// <summary>
-    /// 交易备注
-    /// </summary>
-    [SugarColumn(ColumnName = "remark", Length = 500, IsNullable = true)]
-    public string? Remark { get; set; }
-    
-    /// <summary>
-    /// 交易发生时间
-    /// </summary>
-    [SugarColumn(ColumnName = "transaction_time")]
-    public DateTime TransactionTime { get; set; }
-    
-    /// <summary>
-    /// 记录创建时间
-    /// </summary>
-    [SugarColumn(ColumnName = "created_at")]
-    public DateTime CreatedAt { get; set; }
-}

AssetManager.Data/Position.cs

@@ -0,0 +1,70 @@
+using SqlSugar;
+
+namespace AssetManager.Data;
+
+/// <summary>
+/// 持仓明细表
+/// </summary>
+[SugarTable("positions")]
+public class Position
+{
+    /// <summary>
+    /// 主键
+    /// </summary>
+    [SugarColumn(IsPrimaryKey = true, IsIdentity = false)]
+    public string? Id { get; set; }
+    
+    /// <summary>
+    /// 所属组合ID
+    /// </summary>
+    [SugarColumn(ColumnName = "portfolio_id", IndexGroupNameList = new string[] { "idx_portfolio_id" })]
+    public string? PortfolioId { get; set; }
+    
+    /// <summary>
+    /// 标的代码 (如: UPRO.US)
+    /// </summary>
+    [SugarColumn(ColumnName = "stock_code", Length = 50)]
+    public string? StockCode { get; set; }
+    
+    /// <summary>
+    /// 标的名称
+    /// </summary>
+    [SugarColumn(ColumnName = "stock_name", Length = 200)]
+    public string? StockName { get; set; }
+    
+    /// <summary>
+    /// 资产类型 (Stock/Crypto)
+    /// </summary>
+    [SugarColumn(ColumnName = "asset_type", Length = 20)]
+    public string? AssetType { get; set; }
+    
+    /// <summary>
+    /// 持有数量
+    /// </summary>
+    [SugarColumn(ColumnName = "shares", ColumnDataType = "decimal(18,8)")]
+    public decimal Shares { get; set; }
+    
+    /// <summary>
+    /// 持仓均价
+    /// </summary>
+    [SugarColumn(ColumnName = "avg_price", ColumnDataType = "decimal(18,4)")]
+    public decimal AvgPrice { get; set; }
+    
+    /// <summary>
+    /// 标的币种
+    /// </summary>
+    [SugarColumn(ColumnName = "currency", Length = 10)]
+    public string? Currency { get; set; }
+    
+    /// <summary>
+    /// 建仓时间
+    /// </summary>
+    [SugarColumn(ColumnName = "created_at")]
+    public DateTime CreatedAt { get; set; }
+    
+    /// <summary>
+    /// 最后更新时间
+    /// </summary>
+    [SugarColumn(ColumnName = "updated_at")]
+    public DateTime UpdatedAt { get; set; }
+}

AssetManager.Data/Transaction.cs

@@ -0,0 +1,94 @@
+using SqlSugar;
+
+namespace AssetManager.Data;
+
+/// <summary>
+/// 交易流水表
+/// </summary>
+[SugarTable("transactions")]
+public class Transaction
+{
+    /// <summary>
+    /// 主键
+    /// </summary>
+    [SugarColumn(IsPrimaryKey = true, IsIdentity = false)]
+    public string? Id { get; set; }
+    
+    /// <summary>
+    /// 所属组合ID
+    /// </summary>
+    [SugarColumn(ColumnName = "portfolio_id", IndexGroupNameList = new string[] { "idx_portfolio_id" })]
+    public string? PortfolioId { get; set; }
+    
+    /// <summary>
+    /// 交易类型 (buy/sell)
+    /// </summary>
+    [SugarColumn(ColumnName = "type", Length = 20)]
+    public string? Type { get; set; }
+    
+    /// <summary>
+    /// 标的代码
+    /// </summary>
+    [SugarColumn(ColumnName = "stock_code", Length = 50)]
+    public string? StockCode { get; set; }
+    
+    /// <summary>
+    /// 资产类型 (Stock/Crypto)
+    /// </summary>
+    [SugarColumn(ColumnName = "asset_type", Length = 20)]
+    public string? AssetType { get; set; }
+    
+    /// <summary>
+    /// 交易标题 (如: 定期定投)
+    /// </summary>
+    [SugarColumn(ColumnName = "title", Length = 200)]
+    public string? Title { get; set; }
+    
+    /// <summary>
+    /// 交易数量
+    /// </summary>
+    [SugarColumn(ColumnName = "amount", ColumnDataType = "decimal(18,8)")]
+    public decimal Amount { get; set; }
+    
+    /// <summary>
+    /// 成交价格
+    /// </summary>
+    [SugarColumn(ColumnName = "price", ColumnDataType = "decimal(18,4)")]
+    public decimal Price { get; set; }
+    
+    /// <summary>
+    /// 交易总金额
+    /// </summary>
+    [SugarColumn(ColumnName = "total_amount", ColumnDataType = "decimal(18,4)")]
+    public decimal TotalAmount { get; set; }
+    
+    /// <summary>
+    /// 交易币种
+    /// </summary>
+    [SugarColumn(ColumnName = "currency", Length = 10)]
+    public string? Currency { get; set; }
+    
+    /// <summary>
+    /// 交易状态 (processing/completed)
+    /// </summary>
+    [SugarColumn(ColumnName = "status", Length = 50)]
+    public string? Status { get; set; }
+    
+    /// <summary>
+    /// 交易备注
+    /// </summary>
+    [SugarColumn(ColumnName = "remark", Length = 500, IsNullable = true)]
+    public string? Remark { get; set; }
+    
+    /// <summary>
+    /// 交易发生时间
+    /// </summary>
+    [SugarColumn(ColumnName = "transaction_time")]
+    public DateTime TransactionTime { get; set; }
+    
+    /// <summary>
+    /// 记录创建时间
+    /// </summary>
+    [SugarColumn(ColumnName = "created_at")]
+    public DateTime CreatedAt { get; set; }
+}

AssetManager.Infrastructure/Services/MarketDataService.cs

@@ -33,10 +33,12 @@ public class MarketDataService : IMarketDataService
         _logger = logger;
         _httpClient = httpClientFactory.CreateClient();
         _databaseService = databaseService;
-        // 完全从环境变量读取 Tiingo API Key
+        
+        // 从环境变量读取 Tiingo API Key（必填）
         _tiingoApiKey = Environment.GetEnvironmentVariable("Tiingo__ApiKey")
             ?? Environment.GetEnvironmentVariable("TIINGO_API_KEY")
-            ?? "bd00fee76d3012b047473078904001b33322cb46";
+            ?? throw new InvalidOperationException("Tiingo__ApiKey 环境变量未配置");
+        
         _httpClient.DefaultRequestHeaders.Add("Authorization", $"Token {_tiingoApiKey}");
     }