restore-daemon: make file listing 'streaming'

this prevents an oom kill when listing large directories.
Without this, i'd get an oom kill in the restore vm when
i tried to list a directory with ~60000 entries, but with this,
i'd get the response for even 250000 entries

Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>
Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>

proxmox-restore-daemon/src/proxmox_restore_daemon/api.rs

@@ -116,6 +116,7 @@ fn get_dir_entry(path: &Path) -> Result<DirEntryAttribute, Error> {
 }
 
 #[api(
+    streaming: true,
     input: {
         properties: {
             "path": {