the callback container hardcoded contrast_0's counterpart palette.white,
so the screen rendered white in dark and dim themes. it is a top-level
route with nothing rendered behind it, and body already paints
contrast_0, so the background declaration was redundant as well as wrong.
remove it and let the body background show through.

collapse the paired connect/disconnect and register/unregister methods
into single calls that return their own cleanup, matching the ref-callback
teardown convention used by rows.

the key={currentAccount?.did} fragment only wrapped QueryProvider, whose
own key={currentDid} already remounts the whole subtree on account change
and owns query-cache isolation, so the outer key was a no-op.

drop dead context declarations that were provided but never consumed:
check-email-confirmed, dialog fully-expanded-count, and the video volume
context's muted/setMuted (only volume is read).