Add support for instinct2

[ubipo]

• Add instinct2 (base, s, and crossover) to the manifest
• Use relevant black-and-white icons of correct size
• Support black-and-white colors for the countdown bar (both in glance and app)
• Add a special confirm character (✓) in the TextInput alphabet to confirm without having to long-press select (which doesn't work on instinct2 as it's a shortcut for GPS)
• Fix some unrelated compiler errors that were probably warnings before