Redis will sometimes return a string rather than a number,
in quite a few locations you're doing string vs number comparisons
using the identity operator rather than the equality operator
(so no conversion is done and the types must be equal too).

I've tried a few paths here, but I couldn't find any issues elsewhere.

This was causing an issue in
- /api/users/:userslug/settings
- /api/users/:userslug/favourites
where an explicit equality check for uid/callerUID was done

please keep this pull request open for now, this might have some side-effects