Remove `engine.py`

[AndreasArvidsson]

mimic is not something we should use for anything else than debugging.

Instead of me mimicking "go to sleep" we can just call speech.disable directly

https://github.com/talonhub/community/blob/5b43105de53bae6e489d5b72bf0d6961ae7bb46c/core/engine.py

community/core/modes/modes_not_dragon.talon

Line 31 in 5b43105

^go to sleep [<phrase>]$: speech.disable()

This maybe needs to still exist in some form for dragon users, but it should definitely not be used in modes_not_dragon and we should rename the file to reflect at its dragon only. Ideally we would just remove the file.