feat: 扩展领域模型与配置

src/Domain/TakeoutSaaS.Domain/CustomerService/Entities/ChatMessage.cs

@@ -0,0 +1,45 @@
+using TakeoutSaaS.Domain.CustomerService.Enums;
+using TakeoutSaaS.Shared.Abstractions.Entities;
+
+namespace TakeoutSaaS.Domain.CustomerService.Entities;
+
+/// <summary>
+/// 会话消息。
+/// </summary>
+public sealed class ChatMessage : MultiTenantEntityBase
+{
+    /// <summary>
+    /// 会话标识。
+    /// </summary>
+    public Guid ChatSessionId { get; set; }
+
+    /// <summary>
+    /// 发送方类型。
+    /// </summary>
+    public MessageSenderType SenderType { get; set; } = MessageSenderType.Customer;
+
+    /// <summary>
+    /// 发送方用户 ID。
+    /// </summary>
+    public Guid? SenderUserId { get; set; }
+
+    /// <summary>
+    /// 消息内容。
+    /// </summary>
+    public string Content { get; set; } = string.Empty;
+
+    /// <summary>
+    /// 消息类型（文字/图片/语音等）。
+    /// </summary>
+    public string ContentType { get; set; } = "text/plain";
+
+    /// <summary>
+    /// 是否已读。
+    /// </summary>
+    public bool IsRead { get; set; }
+
+    /// <summary>
+    /// 读取时间。
+    /// </summary>
+    public DateTime? ReadAt { get; set; }
+}