Serve never converts databases: with no paskia.kantadb it points at 'paskia init', or at 'paskia migrate' when legacy *.paskiadb candidates exist. migrate converts a lone candidate, or the one named by --rp-id when several exist; the rest stay in place. devserver fails fast with the same hint. gitignore covers paskia.kantadb and *.converted-bak.