feat: vmtest.sh: the boot loader test for every loader the ISO advertises

One VM per loader, Steam Machine (--fremont): Steamify's state as its menu sees it,
OS name untouched, loader identity, the DKMS modules for every kernel, Steamify's
loader-specific code (hdmi_remove_boot_param), a kernel update, and a reboot into
each of the two kernels. Headless by default with a log Konsole (--window shows
the VMs). Fails when an advertised loader has no test. Limine 41, systemd-boot 40,
GRUB 40 checks pass.

scripts/vmtest.sh

@@ -0,0 +1,42 @@
+#!/bin/bash
+# The whole boot loader test in one command: every boot loader the Steamify ISO
+# advertises, each on its own VM (~/vms/bl-<loader>), one after the other.
+#   scripts/vmtest.sh [--install] [--window] [loader...]     default: all advertised loaders
+#   --install  install each VM first from the newest Steamify ISO (asks before replacing a disk)
+#   --window   show the VMs' windows (default: headless; on a desktop one Konsole follows all the logs)
+# Checks per loader (scripts/vmbootloadertest.sh + share/bootloader-test/):
+#   Steamify's state as its menu sees it, OS name untouched, loader identity,
+#   DKMS modules for every kernel, Steamify's loader-specific code, a kernel
+#   update, a reboot into each kernel. Add a check there, and it runs here.
+# Prints one line per loader and the failed checks; exit status = failures.
+set -uo pipefail
+here="$(cd "$(dirname "$0")" && pwd)"
+repo="$(cd "$here/.." && pwd)"
+iso_repo="$repo/../steammachine-cachyos-live-iso"
+install=""; window=""; loaders=()
+for a in "$@"; do
+    case "$a" in --install) install=--install ;; --window) window=--window ;; *) loaders+=("$a") ;; esac
+done
+# What the ISO advertises: the boot loaders calamares-online.sh keeps.
+advertised="$(sed -n 's/.*"bootloader:\([^"]*\)".*/\1/p' "$iso_repo/archiso/airootfs/usr/local/bin/calamares-online.sh" 2>/dev/null | head -n 1)"
+[[ -n "$advertised" ]] || { echo "Can't read the advertised boot loaders from $iso_repo (calamares-online.sh)" >&2; exit 2; }
+[[ ${#loaders[@]} -gt 0 ]] || read -r -a loaders <<< "$advertised"
+tested="limine systemd-boot grub"   # the loaders vmbootloadertest.sh has a way to boot the other kernel for
+missing=0
+for l in $advertised; do
+    [[ " $tested " == *" $l "* ]] || { echo "FAIL the ISO advertises $l, but there is no test for it (scripts/vmbootloadertest.sh)"; missing=$((missing + 1)); }
+done
+total=$missing
+# No human is needed: headless. One Konsole for all the logs (the loader scripts open none).
+export VMTEST_NO_VIEW=1
+if [[ -z "$window" && -z "${CI:-}" && -n "${WAYLAND_DISPLAY:-}${DISPLAY:-}" ]] && command -v konsole >/dev/null; then
+    logs=(); for l in "${loaders[@]}"; do logs+=("$HOME/vms/bl-$l.test.log"); done
+    systemd-run --user -q --collect --unit="vmtest-view-$$" konsole --hold -e tail -n +1 -F "${logs[@]}" >/dev/null 2>&1 || true
+fi
+for l in "${loaders[@]}"; do
+    "$here/vmbootloadertest.sh" "$l" $install $window > "/tmp/vmtest-$l.out" 2>&1; rc=$?
+    sed -n '/^== /,$p' "/tmp/vmtest-$l.out"
+    total=$((total + rc))
+done
+echo; echo "== total: $total failed check(s) for: ${loaders[*]} (advertised: $advertised)"
+exit "$total"