So we don't need to write so many edge case tests ourselves for things
like parsers, which really don't need those manual tests, as long as we
can check for some properties like "can output the parsed data and it'll
be the same as the input".
One of these was creating a single 262144 byte stack frame. We now have
a way to check and limit the allocation size of a VLA. The `Cmp_Data`
ones were also fairly large. Now, no allocation is larger than 2KiB
(though rtp.c allocates close to that much).
Most system headers contain functions (e.g. `memcpy` in `string.h`)
which aren't needed in our own header files. For the most part, our own
headers should only include types needed to declare our own types and
functions. We now enforce this so we think twice about which headers we
really need in the .h files.
