docs: add query API reference
docs: add query API reference

beetbox/beets,jackwilsdon/beets,beetbox/beets,sampsyo/beets,shamangeorge/beets,SusannaMaria/beets,SusannaMaria/beets,ibmibmibm/beets,jackwilsdon/beets,ibmibmibm/beets,jackwilsdon/beets,ibmibmibm/beets,sampsyo/beets,jackwilsdon/beets,shamangeorge/beets,ibmibmibm/beets,beetbox/beets,sampsyo/beets,SusannaMaria/beets,shamangeorge/beets,shamangeorge/beets,sampsyo/beets,beetbox/beets,SusannaMaria/beets