core: frontend: make progress bars consistent

[ES-Alexander]

Current behaviour

The current progress bar for firmware flashing in the autopilot manager is cyclic (instead of showing actual progress), and looks quite dinky:

Expected or desired behaviour

We've got a lovely progress bar for downloading and extracting docker images, which is used for both BlueOS (core and bootstrap) updates and Extension installations. It would be great to have a similar one for the autopilot downloading, erasing, and flashing process.

Currently the progress can be found as printed updates in the terminal:

but that's not obvious or pleasant for users to access.

Prerequisites

• I have checked to make sure that a similar request has not already been filed or fixed.