fix: 修复前端错误信息丢失 & QQscTool filesetId 提取失败

- 前端 axios 对 HTTP 非2xx直接reject，catch块丢失后端错误信息，从 error.response.data.msg 提取实际错误展示给用户

- QQscTool extractFilesetId 正则未适配 Nuxt 转义JSON格式

web-front/src/components/DirectoryTree.vue

@@ -500,9 +500,14 @@ export default {
             }))
             resolve(children)
           } else {
+            this.$message.error(res.data.msg || '获取子节点失败')
             resolve([])
           }
-        }).catch(() => resolve([]))
+        }).catch(err => {
+          const msg = err.response?.data?.msg || err.message
+          if (msg) this.$message.error(msg)
+          resolve([])
+        })
       } else {
         resolve([])
       }
@@ -540,7 +545,8 @@ export default {
         }
       } catch (error) {
         console.error('进入文件夹失败:', error)
-        this.$message.error('进入文件夹失败')
+        const msg = error.response?.data?.msg || error.message || '进入文件夹失败'
+        this.$message.error(msg)
       } finally {
         this.loading = false
       }
@@ -571,7 +577,8 @@ export default {
         }
       } catch (error) {
         console.error('加载目录失败:', error)
-        this.$message.error('加载目录失败')
+        const msg = error.response?.data?.msg || error.message || '加载目录失败'
+        this.$message.error(msg)
       } finally {
         this.loading = false
       }
@@ -669,7 +676,8 @@ export default {
         }
       } catch (error) {
         console.error('获取下载信息失败:', error)
-        this.$message.error('获取下载信息失败，尝试直接下载')
+        const msg = error.response?.data?.msg || '获取下载信息失败，尝试直接下载'
+        this.$message.error(msg)
         this.downloadFile(file)
       } finally {
         this.downloadLoading = false
@@ -755,7 +763,8 @@ export default {
         }
       } catch (error) {
         console.error('发送到下载器失败:', error)
-        this.$message.error('发送到下载器失败: ' + error.message)
+        const msg = error.response?.data?.msg || error.message || '发送到下载器失败'
+        this.$message.error(msg)
       } finally {
         this.singleSendLoading = false
       }

web-front/src/views/Home.vue

@@ -1157,17 +1157,24 @@ export default {
           params.auth = authParam
         }
         const response = await axios.get(`${this.baseAPI}${endpoint}`, { params })
-        
+
         if (response.data.code === 200) {
           // this.$message.success(response.data.msg || '操作成功')
           return response.data
         } else {
-          // 在页面右下角显示一个“查看详情”按钮 可以查看原json
+          // 在页面右下角显示一个”查看详情”按钮 可以查看原json
           this.errorDetail = response?.data
           this.errorButtonVisible = true
           throw new Error(response.data.msg || '操作失败')
         }
       } catch (error) {
+        // HTTP 非2xx时，从响应体中提取后端返回的错误信息
+        if (error.response?.data?.msg) {
+          this.errorDetail = error.response.data
+          this.errorButtonVisible = true
+          this.$message.error(error.response.data.msg)
+          throw new Error(error.response.data.msg)
+        }
         this.$message.error(error.message || '网络错误')
         throw error
       } finally {

web-front/src/views/ShowFile.vue

@@ -73,7 +73,7 @@ export default {
         this.parseResult = res.data
         this.downloadUrl = res.data.data?.directLink
       } catch (e) {
-        this.error = '解析失败'
+        this.error = e.response?.data?.msg || e.response?.data?.error || '解析失败'
       } finally {
         this.loading = false
       }

web-front/src/views/ShowList.vue

@@ -55,7 +55,7 @@ export default {
         const res = await axios.get('/v2/getFileList', { params: { url: this.url } })
         this.directoryData = res.data.data || []
       } catch (e) {
-        this.error = '目录解析失败'
+        this.error = e.response?.data?.msg || e.response?.data?.error || '目录解析失败'
       } finally {
         this.loading = false
       }