feat(报销/拨款): 进入页面检测OCR服务状态

- 后端新增 GET /ocr-health 端点，探测 Python OCR 服务 /health
- 前端页面 created 时调用健康检查，服务不可用时顶部显示红色警告
  "发票识别服务已停止，请联系信息化部门"
- 服务不可用时禁用附件上传区域（FileUpload 新增 disabled prop）

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

ruoyi-ui/src/components/FileUpload/index.vue

@@ -3,7 +3,7 @@
     <el-upload multiple :drag="dragShow" :action="uploadFileUrl" :before-upload="handleBeforeUpload"
       :file-list="fileList" :limit="limit" :on-error="handleUploadError" :on-exceed="handleExceed"
       :on-success="handleUploadSuccess" :show-file-list="false" :data="{ isPublic: extraData }" :headers="headers"
-      class="upload-file-uploader" ref="fileUpload">
+      :disabled="disabled" class="upload-file-uploader" ref="fileUpload">
       <i class="el-icon-upload" v-if="dragShow"></i>
       <div class="el-upload__text" v-if="dragShow">
         将文件拖到此处，或<em>点击上传</em>
@@ -71,6 +71,10 @@ export default {
     isShowTip: {
       type: Boolean,
       default: true
+    },
+    disabled: {
+      type: Boolean,
+      default: false
     }
   },
   inject: ['$folder'],
@@ -126,6 +130,7 @@ export default {
       this.$download.oss(file.ossId);
     },
     handleBeforeUpload (file) {
+      if (this.disabled) return false;
       const ext = file.name.split('.').pop().toLowerCase();
       if (this.fileType && !this.fileType.includes(ext)) {
         this.$modal.msgError(`文件格式不正确，请上传${this.fileType.join('/')}格式文件！`);