* rfc: migrate app settings as part of export/import/migration * export/import app settings * test, fix * chat: store app settings in db (#3834) * chat: store app settings in db * add combining with app-defaults * commit schema * test with tweaked settings * remove unused error --------- Co-authored-by: Evgeny Poberezkin <evgeny@poberezkin.com> * remove app settings from export/import * test, more settings --------- Co-authored-by: Alexander Bondarenko <486682+dpwiz@users.noreply.github.com>