Playlist : add the possibility to save it with an existing playlist name

Description

Currently, you can only "append" to an existing playlist, but you can't create a new playlist with an existing name.

But the medialibrary support same playlist names, because during scan, you can have multiple playlist with the same filename (playlist.m3u for example)

One use case of this feature is to be able to modify a playlist during playback, directly from the playqueue.

App mode

Smartphone