Introduces dev_vm.sh, a QEMU launcher paired with a minimal archiso-built
dev ISO. The project source is shared read-only into the guest over 9p,
so host edits appear live inside the VM without rebuilding the ISO on
every change. The guest auto-mounts the share at /root/archinstall-dev
and aliases `archinstall` to `python -m archinstall` from that path.
The runtime package list is derived at build time from pyproject.toml
so the script stays in sync with upstream dependencies automatically.
OVMF paths are probed across Arch, Debian/Ubuntu, and Fedora layouts,
and an Arch-based host is verified via /etc/os-release before pacman.
.gitignore: whitelist dev_vm.sh under the existing **/**.sh blanket and
ignore the .dev-iso/ and .dev-configs/ artifact folders.
Softer