[FR] Lyrics page improvements

[AntoninoScordino]

Is your feature request related to a problem? Please describe.
In different user cases, someone might not be interested in keeping lyrics in their music. I've encountered such issues only because I was curious on what the action bar icons below the player did. Currently:

• the lyrics icon is interactable even if no lyrics is present, possibly making the user think otherwise;
• tapping the lyrics icon brings the user to a big tab, which is hard to get out if not by using gestures.
  • With the sentence "hard to get out", I am referencing to the differences between gesture "back" and a simple swipe or back arrow; one might seem like a permanent action (e.g. closing the media player as a whole) and the other is more realistic and understandable.

Describe the solution you'd like

• For the lyrics icon, greying it out when no lyric is present should be enough, accompanied by a toast mentioning how "No lyrics is present for currently playing song";
• for the "getting out" issue, I'd suggest to add a bar on the top, containing album cover, title and author (bonus point if cool animation is included), and add an arrow on the left.
  • This would make it simple to read the lyrics as well, considering that eyes are not going to stay near the status bar (so a little-bit too high), but on the center.

Additional context
The "getting out" issue would be resolved for confused users that do not know how to get out from the empty lyrics page if the first solution would be implemented, due to the page not being openable when no lyrics is found.

• I will open one issue per request, follow the issue format and will add [FR] to the start of my issue title, and I acknowledge that if I don't follow the format, my issue might get closed without further explanation.