Terminal-based graphical playback interface

[RiugaBachi]

For some songs, the ability to view track tabs the traditional ASCII way is still a nice to have.

• As the track is playing, the current note should be highlighted in a color (green maybe?) like in most modern graphical tab players.
• There should also be reload functionality upon source file save; if the new source doesn't compile, keep displaying the previous successfully compiled tab.
• 1-line info bar at the top
  • Current track name
  • Current playback speed
  • Current transpose amount
  • Relevant tab metadata if space allows
• 1-line command input at the bottom
  • Vim-style / search for bar number or marker name
  • Track-switching command
  • Playback speed command
  • Transposing command
• To minimize feature creep, the end user will be expected to maintain additional terminal panes as needed to use the REPL at the same time. All commands added to this TUI should be strictly relevant for session-by-session playback utility.