fix(testing): cleanup traps, arg validation, and two real bugs

Two real bugs and a sweep of hygiene across the harness. `make test`
passed cleanly on this branch with the same 52/0/5 profile as the
2026-05-11 run, so the wiring is verified end-to-end.

Real bugs:

- `lib/vm-utils.sh` `snapshot_exists` was running
  `qemu-img snapshot -l | grep -q "$snapshot_name"`, which matches the
  name as a substring anywhere in the output — including inside dates
  or filenames in other fields. Replaced with an awk field extraction
  on the TAG column plus `grep -Fxq` for a whole-line literal match.
- `run-test-baremetal.sh` was setting `VALIDATION_PASSED=true|false`
  after validation, but `validation.sh` already uses
  `VALIDATION_PASSED` as a pass counter. The test report then
  referenced `$VALIDATION_PASSED_COUNT`, which is defined nowhere.
  Renamed the boolean to `TEST_PASSED` (matching run-test.sh's
  pattern) and report the actual counter.

Cleanup traps and arg validation:

- `run-test.sh` now installs a top-level EXIT trap that, on abort,
  kills QEMU and restores the clean-install snapshot. A
  `CLEANUP_DONE=1` sentinel keeps the existing normal-path cleanup
  from double-firing. This is the recurring pain from 2026-05-11
  where two failed runs left orphaned QEMU processes and dirty base
  disks behind.
- `create-base-vm.sh` and `debug-vm.sh` got the same kind of trap, plus
  `debug-vm.sh` now rejects non-`.qcow2` paths up front instead of
  letting QEMU fail later.
- `run-test.sh`, `run-test-baremetal.sh`, and `cleanup-tests.sh` now
  validate that options with required values actually receive one
  (`${var:?msg}` for `--script`/`--snapshot`/`--host`/`--password`,
  numeric check for `--keep`).
- `run-test-baremetal.sh` traps the temp git bundle for cleanup if the
  script aborts before its explicit `rm`. The ZFS rollback loop now
  uses `while IFS= read -r ds` and quotes `$ds` inside the ssh_cmd so
  dataset names with whitespace wouldn't break it.

Smaller hygiene:

- `vm-utils.sh` `check_ovmf` also checks `OVMF_VARS_TEMPLATE`; `start_qemu`
  validates disk and ISO paths before building the QEMU command;
  numeric tests quoted.
- `cleanup-tests.sh` find expression for temp disks wrapped in
  `\( ... -o ... \)`, all `while read` loops use `IFS= read -r`,
  orphaned QEMU cleanup tries SIGTERM with a 2s sleep before SIGKILL.
- `create-base-vm.sh` moved the "Copy an archangel-*.iso" info line
  before its `fatal` instead of after (unreachable), and added the
  serial-log path to the final summary.
- `lib/logging.sh` `stop_timer` no longer produces `$((end - ))` when
  the named timer was never started.
- `lib/network-diagnostics.sh` `read` → `IFS= read -r`.
- `setup-testing-env.sh` now installs all missing pacman packages in
  one transaction instead of one-at-a-time (avoids half-installed
  state if package N fails). KVM check also verifies the user has
  read+write on `/dev/kvm` and prints the `gpasswd -a $(id -un) kvm`
  fix if not.

A few items from the review I deliberately skipped: replacing the
codebase-wide unquoted `$SSH_OPTS` string with an array (cosmetic, would
need to be done everywhere at once), `set -e` adds where the existing
fall-through-on-failure is intentional, and a `--force` gate on
`create-base-vm.sh` (would break the expected workflow).

1 files changed, 18 insertions, 8 deletions

diff --git a/scripts/testing/setup-testing-env.sh b/scripts/testing/setup-testing-env.sh
index f0e63aa..fb0628b 100755
--- a/scripts/testing/setup-testing-env.sh
+++ b/scripts/testing/setup-testing-env.sh
@@ -45,25 +45,35 @@ PACKAGES=(
     socat
 )
 
+to_install=()
 for pkg in "${PACKAGES[@]}"; do
     if pacman -Qi "$pkg" &>/dev/null; then
         info "$pkg is already installed"
     else
-        step "Installing $pkg"
-        if sudo pacman -S --noconfirm "$pkg" >> "$LOGFILE" 2>&1; then
-            success "$pkg installed"
-        else
-            error "Failed to install $pkg"
-            fatal "Package installation failed"
-        fi
+        to_install+=("$pkg")
     fi
 done
 
+if [ "${#to_install[@]}" -gt 0 ]; then
+    step "Installing in one transaction: ${to_install[*]}"
+    if sudo pacman -S --needed --noconfirm "${to_install[@]}" >> "$LOGFILE" 2>&1; then
+        success "All required packages installed"
+    else
+        fatal "Package installation failed"
+    fi
+fi
+
 # Verify KVM support
 section "Verifying KVM Support"
 
 if [ -e /dev/kvm ]; then
-    success "KVM is available"
+    if [ -r /dev/kvm ] && [ -w /dev/kvm ]; then
+        success "KVM is available and accessible"
+    else
+        warn "KVM exists but is not readable/writable by user $(id -un)"
+        info "Add the user to the kvm group: sudo gpasswd -a $(id -un) kvm"
+        info "Then log out and back in so the new group takes effect"
+    fi
 else
     error "KVM is not available"
     info "Check if virtualization is enabled in BIOS"