Add custom impermanence module

Signed-off-by: Nikolaos Karaolidis <nick@karaolidis.com>

hosts/common/system/configs/impermanence/scripts/start.sh

@@ -0,0 +1,19 @@
+echo "Starting impermanence mount with source: $source, target: $target, path: $path."
+
+source_current="$source"
+target_current="$target"
+
+IFS='/' read -ra path_parts <<< "$path"
+unset "path_parts[-1]"
+
+for part in "${path_parts[@]}"; do
+  source_current="$source_current/$part"
+  target_current="$target_current/$part"
+
+  if [ ! -d "$source_current" ]; then
+    break
+  fi
+
+  read -r mode owner group <<< "$(stat -c '%a %u %g' "$source_current")"
+  install -d -m "$mode" -o "$owner" -g "$group" "$target_current"
+done