Derive Macro stronghold_utils::
Implements the [
VariantPermission] for struct/ unions with PermissionValue(1).
For enums, it implements [
ToPermissionVariants], which creates an according new enum
VariantPermission] by assigning different [
PermissionValue] for each variant.
The permission value is the “index” in the enum as exponent for the power of 2, thus from top to bottom 1, 2, 4,