feat: 新增向量嵌入服务支持

新增SiliconFlow向量嵌入服务实现，支持文本向量化功能：
- 新增ITextEmbeddingService接口和SiliconFlowTextEmbeddingService实现
- 新增EmbeddingCreateRequest/Response等向量相关DTO
- 在AiGateWayManager中新增EmbeddingForStatisticsAsync方法
- 在OpenApiService中新增向量生成API接口
- 扩展ModelTypeEnum枚举支持Embedding类型
- 优化ThorChatMessage的Content属性处理逻辑

Yi.Abp.Net8/module/ai-hub/Yi.Framework.AiHub.Application.Contracts/Dtos/OpenAi/ThorChatMessage.cs

@@ -14,7 +14,6 @@ public class ThorChatMessage
     /// </summary>
     public ThorChatMessage()
     {
-
     }
 
     /// <summary>
@@ -74,20 +73,19 @@ public class ThorChatMessage
         {
             if (value is JsonElement str)
             {
-                if (str.ValueKind == JsonValueKind.String)
-                {
-                    Content = value?.ToString();
-                }
-                else if (str.ValueKind == JsonValueKind.Array)
+                if (str.ValueKind == JsonValueKind.Array)
                 {
                     Contents = JsonSerializer.Deserialize<IList<ThorChatMessageContent>>(value?.ToString());
                 }
             }
+            else if (value is string strInput)
+            {
+                Content = strInput;
+            }
             else
             {
                 Content = value?.ToString();
             }
-
         }
     }
 
@@ -108,15 +106,14 @@ public class ThorChatMessage
     /// </summary>
     [JsonPropertyName("function_call")]
     public ThorChatMessageFunction? FunctionCall { get; set; }
-    
+
     /// <summary>
     /// 【可选】推理内容
     /// </summary>
     [JsonPropertyName("reasoning_content")]
     public string? ReasoningContent { get; set; }
-    
-    [JsonPropertyName("id")]
-    public string? Id { get; set; }
+
+    [JsonPropertyName("id")] public string? Id { get; set; }
 
     /// <summary>
     /// 工具调用列表，模型生成的工具调用，例如函数调用。<br/>
@@ -164,14 +161,15 @@ public class ThorChatMessage
     /// <param name="name">参与者的可选名称。提供模型信息以区分同一角色的参与者。</param>
     /// <param name="toolCalls">工具调用参数列表</param>
     /// <returns></returns>
-    public static ThorChatMessage CreateAssistantMessage(string content, string? name = null, List<ThorToolCall> toolCalls = null)
+    public static ThorChatMessage CreateAssistantMessage(string content, string? name = null,
+        List<ThorToolCall> toolCalls = null)
     {
         return new()
         {
             Role = ThorChatMessageRoleConst.Assistant,
             Content = content,
             Name = name,
-            ToolCalls=toolCalls,
+            ToolCalls = toolCalls,
         };
     }
 
@@ -187,7 +185,7 @@ public class ThorChatMessage
         {
             Role = ThorChatMessageRoleConst.Tool,
             Content = content,
-            ToolCallId= toolCallId
+            ToolCallId = toolCallId
         };
     }
 }