feat(auth): 新增 Apple 登录并集成 Sa-Token 鉴权

- AppleServiceImpl：返回完整用户信息并签发 Sa-Token
- 新增 KeyboardUser 实体、Mapper、Service，支持按 subjectId 查询与创建
- GlobalExceptionHandler 统一处理 Sa-Token 未登录异常
- 补充 APPLE_LOGIN_ERROR 等错误码
- 配置文件增加 Sa-Token 相关参数

src/main/java/com/yolo/keyborad/MyApplication.java

@@ -1,19 +1,28 @@
 package com.yolo.keyborad;
 
+import com.yolo.keyborad.common.xfile.ByteFileWrapperAdapter;
 import com.yolo.keyborad.config.AppleAppStoreProperties;
 import lombok.extern.slf4j.Slf4j;
+import org.dromara.x.file.storage.core.tika.ContentTypeDetect;
+import org.dromara.x.file.storage.spring.EnableFileStorage;
 import org.mybatis.spring.annotation.MapperScan;
 import org.slf4j.LoggerFactory;
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
 import org.springframework.boot.context.properties.EnableConfigurationProperties;
+import org.springframework.context.annotation.Bean;
 
 @Slf4j
 @SpringBootApplication
 @EnableConfigurationProperties(AppleAppStoreProperties.class)
+@EnableFileStorage
 public class MyApplication {
     public static void main(String[] args) {
         SpringApplication.run(MyApplication.class, args);
     }
 
+    @Bean
+    public ByteFileWrapperAdapter byteFileWrapperAdapter(ContentTypeDetect contentTypeDetect) {
+        return new ByteFileWrapperAdapter(contentTypeDetect);
+    }
 }