Add method to set selected option in SendableChooser

[Gold856]

Resolves #3731

[calcmogul]

This doesn't obey the sim/non-sim class split. Users shouldn't be able to call SetSelected() in non-sim robot code (sim objects are no-ops in non-sim).

[Gold856]

Should I wrap it in if (IsSimulation())? I don't like having a whole other class, especially since the other sim classes interact with the HAL, whereas SendableChooser only uses NT. Having a SendableChooserSim means I need an NT publisher to manage, and I'd need to lock it behind if (IsSimulation()) anyways.

[calcmogul]

SendableChooser is still using a key-value system like HALSIM in the form of NT. Teams already complain about how much sim and non-sim code is mixed, and this change conflates them further.

[Starlight220]

Rather than adding a new test, the existing tests should use SendableChooserSim rather than what they do now.

[Starlight220]

Is there value in being able to select from code regardless of sim?

[PeterJohnson]

That’s what the set default option is for. It should theoretically be safe to use NT setDefault() to set the selected value (as this will not override the dashboard set value), but this is not exposed on the Sendable interface.