refactor(phase1): 完成包名重构 (org.example → com.superbiz.agent)

Task 4.1: 包名统一重构
- 重命名 41 个 Java 文件的包名
- 更新所有 import 语句
- 恢复枚举类（FaultCategory、DiagnosisStatus、SourceType）
- 更新测试类的 import

重构范围：
- domain/entity: 3 个实体类
- domain/model: 2 个数据类
- domain/enums: 3 个枚举类
- repository: 3 个接口
- service/session: 2 个类（接口 + 实现）
- config: 9 个配置类
- controller: 2 个控制器
- agent/tool: 4 个工具类
- client: 1 个客户端
- Main.java: 主类

验证结果：
- 编译成功，无错误
- 所有测试通过 (27/27)
  - ApiDocumentRepositoryTest: 7/7 ✅
  - CaseLibraryRepositoryTest: 6/6 ✅
  - DiagnosisRecordRepositoryTest: 6/6 ✅
  - RedisSessionManagerTest: 8/8 ✅

Progress: 21/33 tasks completed (64%)

src/main/java/com/superbiz/agent/controller/FileUploadController.java

@@ -0,0 +1,154 @@
+package com.superbiz.agent.controller;
+
+import com.superbiz.agent.config.FileUploadConfig;
+import com.superbiz.agent.dto.FileUploadRes;
+import com.superbiz.agent.service.VectorIndexService;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.bind.annotation.RestController;
+import org.springframework.web.multipart.MultipartFile;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.Arrays;
+import java.util.List;
+
+@RestController
+public class FileUploadController {
+
+    private static final Logger logger = LoggerFactory.getLogger(FileUploadController.class);
+
+    @Autowired
+    private FileUploadConfig fileUploadConfig;
+
+    @Autowired
+    private VectorIndexService vectorIndexService;
+
+    @PostMapping(value = "/api/upload", consumes = "multipart/form-data")
+    public ResponseEntity<?> upload(@RequestParam("file") MultipartFile file) {
+        if (file.isEmpty()) {
+            return ResponseEntity.badRequest().body("文件不能为空");
+        }
+
+        String originalFilename = file.getOriginalFilename();
+        if (originalFilename == null || originalFilename.isEmpty()) {
+            return ResponseEntity.badRequest().body("文件名不能为空");
+        }
+
+        String fileExtension = getFileExtension(originalFilename);
+        if (!isAllowedExtension(fileExtension)) {
+            return ResponseEntity.status(HttpStatus.BAD_REQUEST)
+                    .body("不支持的文件格式，仅支持: " + fileUploadConfig.getAllowedExtensions());
+        }
+
+        try {
+            String uploadPath = fileUploadConfig.getPath();
+            Path uploadDir = Paths.get(uploadPath).normalize();
+            if (!Files.exists(uploadDir)) {
+                Files.createDirectories(uploadDir);
+            }
+
+            // 使用原始文件名，而不是UUID，以便实现基于文件名的去重
+            Path filePath = uploadDir.resolve(originalFilename).normalize();
+            
+            // 如果文件已存在，先删除旧文件（实现覆盖更新）
+            if (Files.exists(filePath)) {
+                logger.info("文件已存在，将覆盖: {}", filePath);
+                Files.delete(filePath);
+            }
+            
+            Files.copy(file.getInputStream(), filePath);
+
+            logger.info("文件上传成功: {}", filePath);
+
+            // 文件上传成功后，自动调用向量索引服务
+            try {
+                logger.info("开始为上传文件创建向量索引: {}", filePath);
+                vectorIndexService.indexSingleFile(filePath.toString());
+                logger.info("向量索引创建成功: {}", filePath);
+            } catch (Exception e) {
+                logger.error("向量索引创建失败: {}, 错误: {}", filePath, e.getMessage(), e);
+                // 注意：即使索引失败，文件上传仍然成功，只是记录错误日志
+                // 可以根据业务需求决定是否要删除文件或返回错误
+            }
+
+            FileUploadRes response = new FileUploadRes(
+                    originalFilename,
+                    filePath.toString(),
+                    file.getSize()
+            );
+
+            // 使用统一的API响应格式
+            ApiResponse<FileUploadRes> apiResponse = new ApiResponse<>();
+            apiResponse.setCode(200);
+            apiResponse.setMessage("success");
+            apiResponse.setData(response);
+            
+            return ResponseEntity.ok(apiResponse);
+
+        } catch (IOException e) {
+            ApiResponse<String> errorResponse = new ApiResponse<>();
+            errorResponse.setCode(500);
+            errorResponse.setMessage("文件上传失败: " + e.getMessage());
+            return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR)
+                    .body(errorResponse);
+        }
+    }
+
+    /**
+     * 统一 API 响应格式
+     */
+    public static class ApiResponse<T> {
+        private int code;
+        private String message;
+        private T data;
+
+        public int getCode() {
+            return code;
+        }
+
+        public void setCode(int code) {
+            this.code = code;
+        }
+
+        public String getMessage() {
+            return message;
+        }
+
+        public void setMessage(String message) {
+            this.message = message;
+        }
+
+        public T getData() {
+            return data;
+        }
+
+        public void setData(T data) {
+            this.data = data;
+        }
+    }
+
+    private String getFileExtension(String filename) {
+        int lastIndexOf = filename.lastIndexOf(".");
+        if (lastIndexOf == -1) {
+            return "";
+        }
+        return filename.substring(lastIndexOf + 1).toLowerCase();
+    }
+
+    private boolean isAllowedExtension(String extension) {
+        String allowedExtensions = fileUploadConfig.getAllowedExtensions();
+        if (allowedExtensions == null || allowedExtensions.isEmpty()) {
+            return false;
+        }
+        List<String> allowedList = Arrays.asList(allowedExtensions.split(","));
+        return allowedList.contains(extension.toLowerCase());
+    }
+}