So... the answer is no? I don't see anything like that in the Quick Reference (which I have printed and hung on my wall by my desk). I know on Windows you can set keyboard equivalents for menu commands (Mac too, but it's done at the OS level and not in JMP), but I don't see any convenient way to do what I'm describing.
I can set hotkeys to run JSL scripts, but I have no clue how to do those two things with JSL... I'm still learning to think like a JMP user.