Keep procedure functional but hide/remove it from the router type

[ahaubenstock]

Is it possible to mark a procedure as hidden such that it will still work if called but it will not be in the type of the app router export? I did not find anything for this in the docs. I have a use case where I want to allow the procedure to still be functional for old clients, but I want to guarantee that any new clients are not depending on it, ideally by simply removing it and causing type errors wherever it is referenced. Is this doable?