fix(cli): resolve all command name duplication issues

CLI命令重复修复完成（18个命令）：
- interface模块：ssh-start, web-start, webdav-start, iscsi-start, iscsi-stop, iscsi-status
- metadata模块：db-create, db-status, db-backup, db-restore, user-create, user-list, user-show, user-delete, config-show
- storage模块：archive-decompress, archive-list, sync-start, sync-status, mount-attach, mount-detach, mount-list
- interface/tree模块：tree-create, tree-list, tree-import, tree-delete, tree-folder-create, tree-folder-delete, tree-folder-rename

根本原因：
- 所有CLI子模块使用 #[command(flatten)] 导致命令名冲突
- 修复方法：添加 #[command(name = "module-command")] 属性

测试结果：
- ✅ 编译成功（150 warnings, 0 errors）
- ✅ CLI命令列表正确（所有命令在顶层命名空间）
- ✅ SSH服务器启动成功（port 2024）
- ✅ SSH版本交换测试通过（SSH-2.0-MarkBaseSSH_1.0）

影响范围：
- 13个CLI文件修改
- 18个命令添加唯一命名属性
- CLI结构从 interface/metadata/storage/tools 四层变为扁平化单层

markbase-core/src/cli/metadata/db.rs

@@ -4,20 +4,24 @@ use anyhow::Context;
 
 #[derive(Subcommand)]
 pub enum DbCommand {
+    #[command(name = "db-create")]
     Create {
         #[arg(short, long)]
         user: String,
     },
+    #[command(name = "db-status")]
     Status {
         #[arg(short, long)]
         user: String,
     },
+    #[command(name = "db-backup")]
     Backup {
         #[arg(short, long)]
         user: String,
         #[arg(short, long)]
         output: String,
     },
+    #[command(name = "db-restore")]
     Restore {
         #[arg(short, long)]
         user: String,