fix: improve checkpoint UX with proper notifications and persistence info

Issues Fixed:
1. Recovery success notification not showing properly
2. Users uncertain about checkpoint persistence after restart

Improvements:
- Added delay before alert() calls to ensure modals close first
- Added success icons (✅/❌) to all operation notifications
- Added detailed success messages showing checkpoint ID and row counts
- Added informational box explaining checkpoint storage location
- Added cache-busting timestamp to checkpoint list API calls
- Ensured list refresh after create/delete/restore operations

User Experience:
- Clear success/failure feedback for all operations
- Visible confirmation that checkpoints persist across app restarts
- Detailed statistics for each checkpoint operation

This provides clear feedback and transparency about checkpoint management.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

static/db_admin.html

@@ -1271,7 +1271,8 @@
             modal.classList.add('show');
 
             try {
-                const response = await fetch('/fs-ai-asistant/api/workflow/lawrisk/admin/checkpoints');
+                // 添加时间戳参数避免缓存
+                const response = await fetch(`/fs-ai-asistant/api/workflow/lawrisk/admin/checkpoints?t=${Date.now()}`);
                 const data = await response.json();
 
                 if (data.success) {
@@ -1307,6 +1308,16 @@
             const modalBody = document.getElementById('checkpointModalBody');
             let html = '<div class="checkpoint-content">';
 
+            // 信息说明
+            html += `
+                <div class="checkpoint-info" style="background: #e3f2fd; padding: 15px; border-radius: 6px; margin-bottom: 20px; border-left: 4px solid #2196f3;">
+                    <div style="color: #1976d2; font-size: 13px; line-height: 1.6;">
+                        <strong>💡 说明：</strong>检查点文件保存在服务器的 data/checkpoints/ 目录中，重启应用后检查点不会丢失。
+                        每个检查点包含完整的数据库备份，可以随时恢复。
+                    </div>
+                </div>
+            `;
+
             // 创建检查点表单
             html += `
                 <div class="checkpoint-section">
@@ -1383,14 +1394,22 @@
                 const data = await response.json();
 
                 if (data.success) {
-                    alert('检查点创建成功！');
                     document.getElementById('checkpointDescription').value = '';
+                    // 重新加载检查点列表
                     await openCheckpointModal();
+                    // 显示成功消息
+                    setTimeout(() => {
+                        alert(`✅ 检查点创建成功！\n\nID: ${data.data.checkpoint_id}\n备份了 ${data.data.total_rows} 行数据`);
+                    }, 100);
                 } else {
-                    alert(`创建失败：${data.message}`);
+                    setTimeout(() => {
+                        alert(`❌ 创建失败：${data.message}`);
+                    }, 100);
                 }
             } catch (error) {
-                alert(`网络错误：${error.message}`);
+                setTimeout(() => {
+                    alert(`❌ 网络错误：${error.message}`);
+                }, 100);
             } finally {
                 btn.disabled = false;
                 btn.innerHTML = originalText;
@@ -1418,13 +1437,20 @@
                 const data = await response.json();
 
                 if (data.success) {
-                    alert(`检查点恢复成功！\n恢复了 ${data.data.total_rows_restored} 行数据，覆盖了 ${data.data.tables_restored} 个表。`);
+                    // 使用定时器延迟alert，确保modal已关闭
+                    setTimeout(() => {
+                        alert(`✅ 检查点恢复成功！\n\n恢复了 ${data.data.total_rows_restored} 行数据，覆盖了 ${data.data.tables_restored} 个表。`);
+                    }, 100);
                     await openCheckpointModal();
                 } else {
-                    alert(`恢复失败：${data.message}`);
+                    setTimeout(() => {
+                        alert(`❌ 恢复失败：${data.message}`);
+                    }, 100);
                 }
             } catch (error) {
-                alert(`网络错误：${error.message}`);
+                setTimeout(() => {
+                    alert(`❌ 网络错误：${error.message}`);
+                }, 100);
             }
         }
 
@@ -1441,13 +1467,19 @@
                 const data = await response.json();
 
                 if (data.success) {
-                    alert('检查点已删除');
                     await openCheckpointModal();
+                    setTimeout(() => {
+                        alert(`✅ 检查点已删除`);
+                    }, 100);
                 } else {
-                    alert(`删除失败：${data.message}`);
+                    setTimeout(() => {
+                        alert(`❌ 删除失败：${data.message}`);
+                    }, 100);
                 }
             } catch (error) {
-                alert(`网络错误：${error.message}`);
+                setTimeout(() => {
+                    alert(`❌ 网络错误：${error.message}`);
+                }, 100);
             }
         }