- peaceful structure spawns would not run in peaceful mode (e.g., parrots)
- water structure spawns (e.g., guardians) would not run because the code required air above
- small code improvements
Reviewed-on: VoxeLibre/VoxeLibre#4607
Reviewed-by: the-real-herowl <the-real-herowl@noreply.git.minetest.land>
Co-authored-by: kno10 <erich.schubert@gmail.com>
Co-committed-by: kno10 <erich.schubert@gmail.com>