These are some changes I made to debug tooling while tracking down the
bugfix in the previous commit.
Each `scripts/debug_*_alloc.gdb` script has gdb output a `*_allocs.txt`
file, which in turn can be parsed by the `scripts/parse_*_allocs.py`
script to find errors.
I spent some time getting VSCode debugging working. Now I can use VSCode
on windows to work on jsix in Linux (WSL) and launch and debug it within
QEMU. So many layers but it works pretty nicely!