feat: 文传易匿名临时文件传输站初始版本

- 后端 .NET 8 + FreeSql + 阿里云 OSS，支持共享/私密/标签三种文件模式
- 前端 Vue3 + Vite + TDesign，上传/取件/管理三页
- 取件码/二维码/海报合成（含保存二维码为图片）
- deploy/ 部署文档与一键 FTP 发布脚本
- appsettings.json 含真实凭据，已 gitignore 不入库

backend/WenChuanyi.Api/Dtos/FileInfoDto.cs

@@ -0,0 +1,22 @@
+namespace WenChuanyi.Api.Dtos;
+
+/// <summary>文件信息 / 管理列表 / 标签列表 DTO（不暴露密码明文）</summary>
+public class FileInfoDto
+{
+    public long Id { get; set; }
+    public string PickCode { get; set; } = null!;
+    public string FileType { get; set; } = null!;
+    public bool HasPassword { get; set; }
+    public string OriginalName { get; set; } = null!;
+    public long Size { get; set; }
+    public string? MimeType { get; set; }
+    public int DownloadCount { get; set; }
+    /// <summary>上传者 IP（安全审计）：仅管理列表填充，取件/标签/公开接口不暴露</summary>
+    public string? UploadIp { get; set; }
+    public bool IsPermanent { get; set; }
+    public DateTime? ExpiresAt { get; set; }
+    public DateTime CreatedAt { get; set; }
+
+    /// <summary>剩余有效期文本（永久/已过期/N天N小时）</summary>
+    public string ExpireText { get; set; } = "永久";
+}

backend/WenChuanyi.Api/Dtos/OpenApiDtos.cs

@@ -0,0 +1,49 @@
+namespace WenChuanyi.Api.Dtos;
+
+/// <summary>公开上传-共享文件：有效期小时数（0=永久，缺省 24），pwd/tag 可同时提供（不互斥）</summary>
+public class OpenUploadRequest
+{
+    public string FilePath { get; set; } = null!;
+    public long ExpiresHours { get; set; } = 24;
+    public string? Pwd { get; set; }
+    public string? Tag { get; set; }
+}
+
+/// <summary>公开上传-私密文件：必须有密码，可同时带标签</summary>
+public class OpenUploadPriceRequest
+{
+    public string FilePath { get; set; } = null!;
+    public string Pwd { get; set; } = null!;
+    public string? Tag { get; set; }
+}
+
+/// <summary>公开上传-标签文件：必须带标签（永久保存），可同时带密码</summary>
+public class OpenUploadTagRequest
+{
+    public string FilePath { get; set; } = null!;
+    public string Tag { get; set; } = null!;
+    public string? Pwd { get; set; }
+}
+
+/// <summary>公开上传响应</summary>
+public class OpenResult
+{
+    public string PickCode { get; set; } = null!;
+    public string PickUrl { get; set; } = null!;
+    public string DownloadUrl { get; set; } = null!;
+}
+
+/// <summary>公开下载链接查询响应</summary>
+public class OpenDownloadResult
+{
+    public string DownloadUrl { get; set; } = null!;
+    public string PickUrl { get; set; } = null!;
+    public bool NeedPassword { get; set; }
+}
+
+/// <summary>管理删除请求体：按 Id 或取件码删除</summary>
+public class DeleteRequest
+{
+    public long? Id { get; set; }
+    public string? PickCode { get; set; }
+}

backend/WenChuanyi.Api/Dtos/UploadResultDto.cs

@@ -0,0 +1,17 @@
+namespace WenChuanyi.Api.Dtos;
+
+/// <summary>上传响应：取件凭证 + 管理码 + 文件信息</summary>
+public class UploadResultDto
+{
+    public long Id { get; set; }
+    public string PickCode { get; set; } = null!;
+    public string AdminCode { get; set; } = null!;
+    public string FileType { get; set; } = null!;
+    public string OriginalName { get; set; } = null!;
+    public long Size { get; set; }
+    public bool IsPermanent { get; set; }
+    public DateTime? ExpiresAt { get; set; }
+
+    /// <summary>取件页链接（二维码内容）</summary>
+    public string PickUrl { get; set; } = null!;
+}