feat: add wechat mini program mall, check-in supplement and pet skin system

This commit implements a complete WeChat mini program mall and related features:
1. Add pet skin entity and backpack item type support
2. Add make-up check-in and missed date query functions
3. Implement mall product browsing, exchange and record query
4. Add backpack management and item usage (make-up card)
5. Add pet skin equipping function
6. Fix UserBag ItemId type from int to long
7. Adjust Dockerfile exposed port to 8080
8. Fix session cookie unprotect warning

QYZH.InteractiveMagazine.Models/Dto/Bag/UserBagDto.cs

@@ -0,0 +1,87 @@
+namespace QYZH.InteractiveMagazine.Models.Dto.Bag;
+
+/// <summary>
+/// 背包物品输出
+/// </summary>
+public class UserBagOutput
+{
+    public long Id { get; set; }
+    public long ItemId { get; set; }
+    public string ItemType { get; set; } = string.Empty;
+    public int Quantity { get; set; }
+    public string Status { get; set; } = string.Empty;
+
+    /// <summary>
+    /// 关联商品信息（如果有）
+    /// </summary>
+    public BagProductBrief? Product { get; set; }
+
+    /// <summary>
+    /// 关联皮肤信息（PetBg 类型时）
+    /// </summary>
+    public BagSkinBrief? Skin { get; set; }
+
+    public DateTime CreatedAt { get; set; }
+}
+
+/// <summary>
+/// 背包中的商品简要
+/// </summary>
+public class BagProductBrief
+{
+    public string Name { get; set; } = string.Empty;
+    public string? ImageUrl { get; set; }
+    public string? Description { get; set; }
+}
+
+/// <summary>
+/// 背包中的皮肤简要
+/// </summary>
+public class BagSkinBrief
+{
+    public long SkinId { get; set; }
+    public string SkinName { get; set; } = string.Empty;
+    public string? SkinImage { get; set; }
+    public string Rarity { get; set; } = string.Empty;
+}
+
+/// <summary>
+/// 使用物品输入（补签卡）
+/// </summary>
+public class UseItemInput
+{
+    /// <summary>
+    /// 背包物品Id
+    /// </summary>
+    public long BagItemId { get; set; }
+
+    /// <summary>
+    /// 补签目标日期（yyyy-MM-dd，仅补签卡使用）
+    /// </summary>
+    public string? TargetDate { get; set; }
+}
+
+/// <summary>
+/// 换肤输入
+/// </summary>
+public class EquipSkinInput
+{
+    /// <summary>
+    /// 皮肤Id（传0则恢复默认皮肤）
+    /// </summary>
+    public long SkinId { get; set; }
+}
+
+/// <summary>
+/// 使用物品输出
+/// </summary>
+public class UseItemOutput
+{
+    public bool IsSuccess { get; set; }
+    public string Message { get; set; } = string.Empty;
+
+    /// <summary>
+    /// 补签时返回的签到结果
+    /// </summary>
+    public object? Extra { get; set; }
+}

QYZH.InteractiveMagazine.Models/Dto/Mall/WxMallDto.cs

@@ -0,0 +1,80 @@
+namespace QYZH.InteractiveMagazine.Models.Dto.Mall;
+
+/// <summary>
+/// 小程序商品展示输出
+/// </summary>
+public class WxProductOutput
+{
+    public long Id { get; set; }
+    public string Name { get; set; } = string.Empty;
+    public string? Description { get; set; }
+    public string? ImageUrl { get; set; }
+    public int Price { get; set; }
+    public string Type { get; set; } = string.Empty;
+
+    /// <summary>
+    /// 皮肤信息（仅 PetBg 类型有值）
+    /// </summary>
+    public PetSkinBrief? Skin { get; set; }
+
+    /// <summary>
+    /// 用户是否已拥有（PetBg 类型时判断背包中是否有）
+    /// </summary>
+    public bool Owned { get; set; }
+}
+
+/// <summary>
+/// 皮肤简要信息
+/// </summary>
+public class PetSkinBrief
+{
+    public long SkinId { get; set; }
+    public string SkinName { get; set; } = string.Empty;
+    public string? SkinImage { get; set; }
+    public string? Description { get; set; }
+    public string Rarity { get; set; } = string.Empty;
+}
+
+/// <summary>
+/// 兑换输入
+/// </summary>
+public class ExchangeInput
+{
+    /// <summary>
+    /// 商品Id
+    /// </summary>
+    public long ProductId { get; set; }
+
+    /// <summary>
+    /// 兑换数量（默认1）
+    /// </summary>
+    public int Quantity { get; set; } = 1;
+}
+
+/// <summary>
+/// 兑换输出
+/// </summary>
+public class ExchangeOutput
+{
+    public long RecordId { get; set; }
+    public string ProductName { get; set; } = string.Empty;
+    public int PointsCost { get; set; }
+    public int PointsBalance { get; set; }
+    public string Message { get; set; } = string.Empty;
+}
+
+/// <summary>
+/// 兑换记录输出
+/// </summary>
+public class ExchangeRecordOutput
+{
+    public long Id { get; set; }
+    public long ProductId { get; set; }
+    public string ProductName { get; set; } = string.Empty;
+    public string ProductType { get; set; } = string.Empty;
+    public int PointsCost { get; set; }
+    public int PointsBalance { get; set; }
+    public int Quantity { get; set; }
+    public string Status { get; set; } = string.Empty;
+    public DateTime CreatedAt { get; set; }
+}