update return types, remove already type-hinted params with no description
update return types, remove already type-hinted params with no description

ppy/osu-web,ppy/osu-web,ppy/osu-web,notbakaneko/osu-web,notbakaneko/osu-web,notbakaneko/osu-web,notbakaneko/osu-web,ppy/osu-web,notbakaneko/osu-web,ppy/osu-web