The previous naming convention was confusing because it did not make
it explicit that the string is not being copied. We had this wrong already
in the Lua bindings and thanks to some miracle it hasn't backfired so far
(it was using the "wrap" behaviour with a string that doesn't stay alive).
In some places we actually need the "copy" behaviour and in some other
places we need the "wrap" behaviour, so let's have both variants available.
The purpose is to wrap some utilities that pipewire provides that use JSON.
Start by wrapping pw_conf_match_rules(), which despite its name, it has nothing
to do with the configuration object. It operates directly on JSON and can be
useful to work with match rules outside the context of configuration files.