feat: add speed factor sensor

[TheJefe]

Description

This PR adds a simple speed_factor sensor
API Documentation: https://www.klipper3d.org/Status_Reference.html#gcode_move

Additionally, It is maybe worth noting that I am using a Sonic Pad, and having no issues with this project

Testing

Tested on my local HA setup, works exactly as expected

Other

Not included in this PR, I added some macros and buttons to adjust the speed factor

[marcolivierarsenault]

@TheJefe please 👁️ the tests

[TheJefe]

@marcolivierarsenault , sorry for the delay, but I fixed the tests

[marcolivierarsenault]

@TheJefe

To fix formating make sure pre-commit hook works.

else you can run black manually black .

[marcolivierarsenault]

Make sure you have black pass and

add some test for your new sensors.
(AKA, add parameters to test_sensors in test_sensors.py file.)

adding

        ("mainsail_speed_factor", "200.0"),

should do the trick

[TheJefe]

Thanks for the guidance @marcolivierarsenault ! I've made the requested updates

[marcolivierarsenault]

This look great, will do final review and merge later this weekend

[marcolivierarsenault]

Thank you @TheJefe