refactor: 将 AnthropicInput.InputSchema 改为 object 并移除相关强类型定义

将原来的 Input_schema、InputSchemaValue 等强类型移除，AnthropicInput 中的 input_schema 属性类型由 Input_schema? 改为 object?，用于接受任意结构的输入 schema，简化序列化/反序列化处理。

Yi.Abp.Net8/module/ai-hub/Yi.Framework.AiHub.Domain.Shared/Dtos/Anthropic/AnthropicInput.cs

@@ -133,28 +133,5 @@ public class AnthropicMessageTool
 
     [JsonPropertyName("description")] public string? Description { get; set; }
 
-    [JsonPropertyName("input_schema")] public Input_schema? InputSchema { get; set; }
-}
-
-public class Input_schema
-{
-    [JsonPropertyName("type")] public string? Type { get; set; }
-
-    [JsonPropertyName("properties")] public Dictionary<string, InputSchemaValue>? Properties { get; set; }
-
-    [JsonPropertyName("required")] public string[]? Required { get; set; }
-}
-
-public class InputSchemaValue
-{
-    public string? type { get; set; }
-
-    public string? description { get; set; }
-
-    public InputSchemaValueItems? items { get; set; }
-}
-
-public class InputSchemaValueItems
-{
-    public string? type { get; set; }
+    [JsonPropertyName("input_schema")] public object? InputSchema { get; set; }
 }