Add option for default subtitle and audio track languages

We want a global default like in the desktop versions of VLC. Additionally, we want to retain the last track languages per media item in the media library.

changed milestone to %Future

added Beginner friendly Feature MediaLibrary + 1 deleted label

mentioned in merge request !236 (closed)

marked vlc#14031 (closed) as a duplicate of this issue

marked this issue as related to vlc#14031 (closed)

changed milestone to %4.0.0