[compiler] validation against calling impure functions (#31960)

For now we just reject all calls of impure functions, and the validation
is off by default. Going forward we can make this more precise and only
reject impure functions called during render.

Note that I was intentionally imprecise in the return type of these
functions in order to avoid changing output of existing code. We lie to
the compiler and say that Date.now, performance.now, and Math.random
return unknown mutable objects rather than primitives. Once the
validation is complete and vetted we can switch this to be more precise.