Implement the currently playing song "crumbar" (UI)

[sebastian-nunez]

Description

We want to show users their currently playing song as well as the ability to pause it.

Acceptance Criteria

• Users can see the currently playing song crumbar right above the main tab bar
• Users are able to see song title and artist name of the song playing
• Users are able to pause/play the song directly from the crumbar

[sebastian-nunez]

Closed by PR #46