status: fix false DRIFT for non-root invocations

- runner: export sbin-inclusive PATH (util-linux tools live in /usr/sbin)
- 001: read /proc/swaps instead of swapon(8)
- 005: resolve /dev/disk/by-uuid symlink instead of findfs(8); report ?
  (exit 2) when the UUID cannot be resolved

migrations/001-create-swap.sh

@@ -26,8 +26,7 @@ case "${1:-}" in
     echo "    swap 2GB enabled + fstab entry + vm.swappiness=10"
     ;;
   status)
-    swapon --show --noheadings 2>/dev/null | grep -q '^/swapfile ' \
-      || { echo "DRIFT /swapfile not active"; exit 1; }
+    grep -q '^/swapfile ' /proc/swaps || { echo "DRIFT /swapfile not active"; exit 1; }
     grep -q '^/swapfile ' /etc/fstab || { echo "DRIFT fstab entry missing"; exit 1; }
     swp=$(cat /proc/sys/vm/swappiness 2>/dev/null || echo '?')
     [[ $swp == 10 ]] || { echo "DRIFT vm.swappiness=$swp (want 10)"; exit 1; }