feat(marketing): add full reduction campaign api module

src/Application/TakeoutSaaS.Application/App/Coupons/FullReduction/Dto/FullReductionRulesDto.cs

@@ -0,0 +1,62 @@
+namespace TakeoutSaaS.Application.App.Coupons.FullReduction.Dto;
+
+/// <summary>
+/// 满减活动规则 DTO。
+/// </summary>
+public sealed class FullReductionRulesDto
+{
+    /// <summary>
+    /// 活动类型（reduce/gift/second_half）。
+    /// </summary>
+    public string ActivityType { get; init; } = "reduce";
+
+    /// <summary>
+    /// 满减阶梯。
+    /// </summary>
+    public IReadOnlyList<FullReductionTierRuleDto> ReduceTiers { get; init; } = [];
+
+    /// <summary>
+    /// 满赠规则。
+    /// </summary>
+    public FullReductionGiftRuleDto? GiftRule { get; init; }
+
+    /// <summary>
+    /// 第二份半价规则。
+    /// </summary>
+    public FullReductionSecondHalfRuleDto? SecondHalfRule { get; init; }
+
+    /// <summary>
+    /// 适用渠道。
+    /// </summary>
+    public IReadOnlyList<string> Channels { get; init; } = [];
+
+    /// <summary>
+    /// 门店范围模式（all/stores）。
+    /// </summary>
+    public string StoreScopeMode { get; init; } = "all";
+
+    /// <summary>
+    /// 门店范围 ID。
+    /// </summary>
+    public IReadOnlyList<long> StoreIds { get; init; } = [];
+
+    /// <summary>
+    /// 选品基准门店 ID。
+    /// </summary>
+    public long ScopeStoreId { get; init; }
+
+    /// <summary>
+    /// 是否可叠加优惠券。
+    /// </summary>
+    public bool StackWithCoupon { get; init; }
+
+    /// <summary>
+    /// 活动说明。
+    /// </summary>
+    public string? Description { get; init; }
+
+    /// <summary>
+    /// 统计指标。
+    /// </summary>
+    public FullReductionMetricsDto Metrics { get; init; } = new();
+}