Improve UX for editing programs

[tmarsteel]

There are multiple states the App can be in, and the UI still doesn't nicely distinguish between all of them. May also make sense to remove some, for simplicity.

• Amp not connected
  • an unassociated program is seen and can be edited
  • viewing a saved program, but cannot be edited
• Amp connected
  • amp program slot is selected, respective program is shown and can be edited
  • amp program slot is selected, program from another slot is shown and can be edited. Doesn't sync to the AMP
  • amp program slot is selected, saved program is shown and [can be edited?]