Stride: GameTime needs more options

[Basewq]

Is your feature request related to a problem? Please describe.
Maybe or maybe not the GameTime class itself, but there needs to be more features to control the 'timer' of a game.
A game needs options be able to pause a game, scale the timer (eg. for slow motion).
This also needs to be affect the physics engine, model animation, but NOT the UI (though not sure if UI has any built in animations?).
Not sure how Sound should be affected.

While you can just create your own "GameTime" object that your own scripts can use, this doesn't affect physics/animation since they specifically use GameTime.
Physics only has Simulation.DisableSimulation, but no time scale, though there is a FixedTimeStep field, but not sure if that is really the appropriate thing to change for time scaling.

Describe the solution you'd like
Honestly don't know what the solution is for this.
I know Unity uses a static field (bleh!) Time.timeScale.
Perhaps be able to set it directly on the GameTime object itself, or maybe via a service/game system?
One thing that needs to be clear if done is ensuring there's a distinction between the _current_ time's scale and the _requested change_ in time scale.

[ykafia]

I'll have a go on this issue and see what i can do.