[ADD] base: enhanced security mode for users

Similar to github's sudo mode, my understanding of the intent is to
avoid third parties being able to perform sensitive / serious
operations when leaving a logged-in machine unattended.

This v1 only handles protecting "action methods" (methods called
through buttons and intended to return action descriptors), although
they can be used to "lock out" any methods they won't be able to
prompt and the caller will likely be surprised.