feat: 扩展领域模型与配置

src/Domain/TakeoutSaaS.Domain/Analytics/Entities/MetricDefinition.cs

@@ -0,0 +1,34 @@
+using TakeoutSaaS.Shared.Abstractions.Entities;
+
+namespace TakeoutSaaS.Domain.Analytics.Entities;
+
+/// <summary>
+/// 指标定义，描述可观测的数据点。
+/// </summary>
+public sealed class MetricDefinition : MultiTenantEntityBase
+{
+    /// <summary>
+    /// 指标编码。
+    /// </summary>
+    public string Code { get; set; } = string.Empty;
+
+    /// <summary>
+    /// 指标名称。
+    /// </summary>
+    public string Name { get; set; } = string.Empty;
+
+    /// <summary>
+    /// 说明。
+    /// </summary>
+    public string? Description { get; set; }
+
+    /// <summary>
+    /// 维度描述 JSON。
+    /// </summary>
+    public string? DimensionsJson { get; set; }
+
+    /// <summary>
+    /// 默认聚合方式。
+    /// </summary>
+    public string DefaultAggregation { get; set; } = "sum";
+}