Have an event for changing kernels, or don't allow if a debugging session is active #7180
Description
If a user changes the kernel while a debug session is active, they get stuck in a glitched state. The debug session needs to be disconnected before that.
IKernel has an onDisposed, but that is too late.
We need to either have an event that the DebuggingManager can catch to disconnect, or prevent the user of being able to change the kernel while debugging.