installed windows client save incoming recording to a specific directory (#7974)

Signed-off-by: 21pages <pages21@163.com>

flutter/lib/web/bridge.dart

@@ -943,7 +943,7 @@ class RustdeskImpl {
     throw UnimplementedError();
   }
 
-  Future<String> mainDefaultVideoSaveDirectory({dynamic hint}) {
+  Future<String> mainVideoSaveDirectory({required bool root, dynamic hint}) {
     throw UnimplementedError();
   }