feat: 新增 SAP HANA 数据库备份支持和 FTP 存储后端

后端变更：
- 新增 SAP HANA 备份 Runner (saphana_runner.go)，使用 hdbsql CLI 工具执行数据库导出/恢复
- 新增 FTP 存储 Provider (storage/ftp/provider.go)，支持 FTP/FTPS 协议上传下载备份文件
- 在 storage/types.go 中添加 FTP 类型常量和 FTPConfig 配置结构
- 在 app.go 中注册 FTP Storage Factory 和 SAP HANA Backup Runner
- 添加 github.com/jlaffaye/ftp 依赖

前端变更：
- BackupTaskType 联合类型新增 'saphana'，默认端口 30015
- StorageTargetType 联合类型新增 'ftp'
- 备份任务表单支持 SAP HANA 类型选择及数据库连接配置
- 存储目标表单新增 FTP 配置字段（主机/端口/用户名/密码/基础目录/TLS）

参考：backint_minio1.0.0/ Java 实现

web/src/components/backup-tasks/BackupTaskFormDrawer.tsx

@@ -106,11 +106,11 @@ export function BackupTaskFormDrawer({ visible, loading, initialValue, storageTa
       type: value,
       sourcePath: value === 'file' ? current.sourcePath : '',
       excludePatterns: value === 'file' ? current.excludePatterns : [],
-      dbHost: value === 'mysql' || value === 'postgresql' ? current.dbHost : '',
-      dbPort: value === 'mysql' || value === 'postgresql' ? current.dbPort || getDefaultPort(value) : 0,
-      dbUser: value === 'mysql' || value === 'postgresql' ? current.dbUser : '',
-      dbPassword: value === 'mysql' || value === 'postgresql' ? current.dbPassword : '',
-      dbName: value === 'mysql' || value === 'postgresql' ? current.dbName : '',
+      dbHost: value === 'mysql' || value === 'postgresql' || value === 'saphana' ? current.dbHost : '',
+      dbPort: value === 'mysql' || value === 'postgresql' || value === 'saphana' ? current.dbPort || getDefaultPort(value) : 0,
+      dbUser: value === 'mysql' || value === 'postgresql' || value === 'saphana' ? current.dbUser : '',
+      dbPassword: value === 'mysql' || value === 'postgresql' || value === 'saphana' ? current.dbPassword : '',
+      dbName: value === 'mysql' || value === 'postgresql' || value === 'saphana' ? current.dbName : '',
       dbPath: value === 'sqlite' ? current.dbPath : '',
     }))
     if (value !== 'file') {

web/src/components/backup-tasks/field-config.ts

@@ -5,6 +5,7 @@ export const backupTaskTypeOptions = [
   { label: 'MySQL', value: 'mysql' },
   { label: 'SQLite', value: 'sqlite' },
   { label: 'PostgreSQL', value: 'postgresql' },
+  { label: 'SAP HANA', value: 'saphana' },
 ] as const
 
 export const backupCompressionOptions = [
@@ -22,6 +23,8 @@ export function getBackupTaskTypeLabel(type: BackupTaskType) {
       return 'SQLite'
     case 'postgresql':
       return 'PostgreSQL'
+    case 'saphana':
+      return 'SAP HANA'
     default:
       return type
   }
@@ -64,7 +67,7 @@ export function isSQLiteBackupTask(type: BackupTaskType) {
 }
 
 export function isDatabaseBackupTask(type: BackupTaskType) {
-  return type === 'mysql' || type === 'postgresql'
+  return type === 'mysql' || type === 'postgresql' || type === 'saphana'
 }
 
 export function getDefaultPort(type: BackupTaskType) {
@@ -73,6 +76,8 @@ export function getDefaultPort(type: BackupTaskType) {
       return 3306
     case 'postgresql':
       return 5432
+    case 'saphana':
+      return 30015
     default:
       return 0
   }