更新附件追加功能，优化文件选择和验证逻辑，支持多种文件格式，调整用户界面以提升操作体验。

app/routes/documents._index.tsx

@@ -1064,11 +1064,11 @@ export default function DocumentsIndex() {
             <i className="ri-download-line"></i>
             下载
           </button>
-          {record.type === 1 && record.fileStatus === 'Processed' && (
+          {record.type === '1' && record.fileStatus === 'Processed' && (
             <>
               <button 
                 type="button"
-                className="text-xs px-2 py-1 h-7 mr-1 bg-primary text-white hover:bg-primary-dark rounded"
+                className="text-xs px-2 py-1 h-7 mr-1 hover:underline hover:text-primary"
                 onClick={() => {
                   setSelectedDocumentId(record.id);
                   setShowAttachmentUpload(true);
@@ -1079,7 +1079,7 @@ export default function DocumentsIndex() {
               </button>
               <button 
                 type="button"
-                className="text-xs px-2 py-1 h-7 mr-1 bg-gray-100 text-gray-700 hover:bg-gray-200 rounded"
+                className="text-xs px-2 py-1 h-7 mr-1 text-gray-500 hover:underline hover:text-gray-700"
                 onClick={() => {
                   setSelectedDocumentId(record.id);
                   setShowTemplateUpload(true);