添加项目文件。

MessageService.WebApi/Application/Dtos/ConversationResponse.cs

@@ -0,0 +1,35 @@
+using MessageService.Domain.Enums;
+
+namespace MessageService.WebApi.Application.Dtos
+{
+    public class ConversationResponse
+    {
+        public Guid Id { get; set; }
+        public Guid UserId { get; set; }
+
+        /// <summary>
+        /// 对方ID（群聊为群聊ID，单聊为单聊ID）	
+        /// </summary>
+        public Guid TargetId { get; set; }
+        public string TargetAvatar { get; set; }
+        public string TargetName { get; set; }
+
+        /// <summary>
+        /// 最后一条未读消息ID	
+        /// </summary>
+        public long? LastReadSequenceId { get; set; }
+
+        /// <summary>
+        /// 未读消息数	
+        /// </summary>
+        public int UnreadCount { get; set; }
+
+        public ChatType ChatType { get; set; }
+
+
+        /// <summary>
+        /// 最后一条最新消息
+        /// </summary>
+        public string LastMessage { get; set; }
+    }
+}

MessageService.WebApi/Application/Dtos/GetMessagesResponse.cs

@@ -0,0 +1,14 @@
+namespace MessageService.WebApi.Application.Dtos
+{
+    public class GetMessagesResponse
+    {
+        public List<MessageResponse> Messages { get; init; }
+        public bool Hasmore { get; init; }
+
+        public GetMessagesResponse(List<MessageResponse> messages, bool hasmore)
+        {
+            Messages = messages;
+            Hasmore = hasmore;
+        }
+    }
+}

MessageService.WebApi/Application/Dtos/MessageResponse.cs

@@ -0,0 +1,36 @@
+using MessageService.Domain.Enums;
+
+namespace MessageService.WebApi.Application.Dtos
+{
+    public record MessageResponse
+    {
+        public Guid Id { get; init; }
+        public Guid ClientMsgId { get; init; }
+        public ChatType ChatType { get; init; }
+        public MessageType MsgType { get; init; }
+        public Guid SenderId { get; init; }
+        public Guid TargetId { get; init; }
+        public MessageState State { get; init; }
+        public string StreamKey { get; init; }
+        public long SequenceId { get; init; }
+        public DateTimeOffset CreationTime { get; init; }
+
+        // 关键：展开 Content
+        public MessageContentResponse Content { get; init; }
+    }
+
+    public record MessageContentResponse(
+        string Fallback,
+        object Body, // 已经是反序列化后的具体对象
+        Dictionary<string, string> Ext,
+        QuoteInfoResponse? Quote
+    );
+
+    public record QuoteInfoResponse(
+        Guid MessageId,
+        Guid SenderId,
+        string SenderName,
+        MessageType MessageType,
+        string Preview
+    );
+}