Out of bounds handling for non-US keyboards

[paradoxheart]

For the most part a UK layout keyboard works on Vinix, but certain keys will trigger a panic. For example, when typing a pipe character:

V panic: array.get: index out of range (i == 86, a.len == 58)
v hash: bfcf5b1

I suggest for all keys that cannot be mapped, that U+FFFD � REPLACEMENT CHARACTER is emitted.