* Add two debugutils procs that native debuggers can break on use to
execute commands when code of interest is being compiled.
* Add GDB and LLDB programs to disable and enable breakpoints and
watchpoints when code of interest is being compiled.
* Extend the `intern.rst` docs regarding debugging the compiler.
Co-authored-by: quantimnot <quantimnot@users.noreply.github.com>
