Add sin, cos and tan maths functions

[peternewman]

Also update:

• https://github.com/bitfocus/companion/blob/main/docs/user-guide/4_expressions/functions.md - Add docs for new maths functions companion#4388
• https://github.com/bitfocus/companion/blob/main/webui/src/Resources/Expression.monarch.ts - Add docs for new maths functions companion#4388

[Julusian]

should we also have arcsine and things too?

my maths thoery is pretty rusty, so dont remember what the useful things are

[peternewman]

should we also have arcsine and things too?

Probably, these all appear in useful looking places on a triangle:
https://en.wikipedia.org/wiki/Inverse_trigonometric_functions

my maths thoery is pretty rusty, so dont remember what the useful things are

Mine isn't great either TBH!

I guess it's a bit of a case of where we stop! I see cube root is also missing too for example...