This does a slight cleanup on the Now playing notifications as mentioned on Discord:

• The notification text isn't localised and would be a general PITA to localise in the first place
• The whole point of this notification showing up is that the song is now playing, meaning "Now playing" in the text is redundant and therefore unnecessary
• I don't know any other music player notification that shows this, for reference this is DeaDBeeF:
  
• Formatted the layout to mimic the in-player Now Playing display

Note I didn't test this with Feishin itself cause I don't currently have a setup to actually compile it, but I did test the strings with notify-send and it worked just fine:

Tested with CI artifact and works as expected.
Can't test Windows or Mac though.