Add Bessel filter

[ufechner7]

See: https://en.wikipedia.org/wiki/Bessel_filter

A Bessel filter is required if you need a filtered signal, but want to avoid any overshoot.

https://electronics.stackexchange.com/questions/521118/why-do-reverse-bessel-polynomials-give-rise-to-flat-group-delay-in-bessel-filter/521155#521155

https://github.com/scipy/scipy/blob/e29dcb65a2040f04819b426a04b60d44a8f69c04/scipy/signal/_filter_design.py#L3604

https://www.perplexity.ai/search/can-you-provide-code-for-a-dig-01q15d17RZKnx_a0vhQF5A