feat(faq): support rich-text image upload and RAG output

- add FAQ image upload API with MinIO path and mime/size validation

- enable FAQ editor image upload and text-or-image validation

- include FAQ image metadata in vector content and retrieval output

- enforce markdown image preservation via bot system prompt rule

easyflow-api/easyflow-api-admin/src/main/java/tech/easyflow/admin/controller/ai/FaqItemController.java

@@ -4,31 +4,56 @@ import cn.dev33.satoken.annotation.SaCheckPermission;
 import com.mybatisflex.core.paginate.Page;
 import com.mybatisflex.core.query.QueryWrapper;
 import jakarta.servlet.http.HttpServletRequest;
+import org.springframework.http.MediaType;
+import org.springframework.util.StringUtils;
 import org.springframework.web.bind.annotation.GetMapping;
 import org.springframework.web.bind.annotation.PostMapping;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
+import org.springframework.web.multipart.MultipartFile;
+import tech.easyflow.ai.entity.DocumentCollection;
 import tech.easyflow.ai.entity.FaqItem;
+import tech.easyflow.ai.service.DocumentCollectionService;
 import tech.easyflow.ai.service.FaqCategoryService;
 import tech.easyflow.ai.service.FaqItemService;
 import tech.easyflow.common.annotation.UsePermission;
 import tech.easyflow.common.domain.Result;
+import tech.easyflow.common.filestorage.FileStorageService;
+import tech.easyflow.common.vo.UploadResVo;
 import tech.easyflow.common.web.controller.BaseCurdController;
 import tech.easyflow.common.web.exceptions.BusinessException;
 import tech.easyflow.common.web.jsonbody.JsonBody;
 
+import javax.annotation.Resource;
 import java.io.Serializable;
 import java.math.BigInteger;
+import java.util.Arrays;
+import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 
 @RestController
 @RequestMapping("/api/v1/faqItem")
 @UsePermission(moduleName = "/api/v1/documentCollection")
 public class FaqItemController extends BaseCurdController<FaqItemService, FaqItem> {
 
+    private static final long MAX_IMAGE_SIZE_BYTES = 5L * 1024L * 1024L;
+    private static final Set<String> ALLOWED_IMAGE_TYPES = new HashSet<>(Arrays.asList(
+            "image/jpeg",
+            "image/png",
+            "image/webp",
+            "image/gif"
+    ));
+
     private final FaqCategoryService faqCategoryService;
 
+    @Resource
+    private DocumentCollectionService documentCollectionService;
+
+    @Resource(name = "default")
+    private FileStorageService fileStorageService;
+
     public FaqItemController(FaqItemService service, FaqCategoryService faqCategoryService) {
         super(service);
         this.faqCategoryService = faqCategoryService;
@@ -118,8 +143,43 @@ public class FaqItemController extends BaseCurdController<FaqItemService, FaqIte
         return Result.ok(service.removeFaqItem(new java.math.BigInteger(String.valueOf(id))));
     }
 
+    @PostMapping(value = "uploadImage", produces = MediaType.APPLICATION_JSON_VALUE)
+    @SaCheckPermission("/api/v1/documentCollection/save")
+    public Result<UploadResVo> uploadImage(MultipartFile file, BigInteger collectionId) {
+        if (collectionId == null) {
+            throw new BusinessException("知识库ID不能为空");
+        }
+        if (file == null || file.isEmpty()) {
+            throw new BusinessException("图片不能为空");
+        }
+        if (file.getSize() > MAX_IMAGE_SIZE_BYTES) {
+            throw new BusinessException("图片大小不能超过5MB");
+        }
+        if (!isAllowedImageType(file)) {
+            throw new BusinessException("仅支持 JPG/PNG/WEBP/GIF 图片");
+        }
+
+        DocumentCollection collection = documentCollectionService.getById(collectionId);
+        if (collection == null) {
+            throw new BusinessException("知识库不存在");
+        }
+        if (!collection.isFaqCollection()) {
+            throw new BusinessException("当前知识库不是FAQ类型");
+        }
+
+        String path = fileStorageService.save(file, "faq/" + collectionId);
+        UploadResVo resVo = new UploadResVo();
+        resVo.setPath(path);
+        return Result.ok(resVo);
+    }
+
     @Override
     protected String getDefaultOrderBy() {
         return "order_no asc";
     }
+
+    private boolean isAllowedImageType(MultipartFile file) {
+        String contentType = file.getContentType();
+        return StringUtils.hasText(contentType) && ALLOWED_IMAGE_TYPES.contains(contentType.toLowerCase());
+    }
 }