refactor cli_handler to use engine pattern

[aastopher]

arg parse will be the first and only engine at first with rich to come in a future version

[aastopher]

moved this to 0.2.1 as this would be major rework of the CLI class also involving developing supporting classes

[aastopher]

this will be a major refactor for clarity argparse will be dropped for click and rich-click. Structural changes will be made for code cleanliness. Since click definitions are already pretty concise the focus will be to create use through annotations and compress group definitions this will also solve cross context method calls with unwrapping.