fix(developer): URL parameters should be UTF-8

Fixes #7628.

Indy components do not treat URLs as UTF-8. Our legacy EncodeURL
function (sourced from Indy components) was the same. Discovered we
needed to fixup the parsing of URLs as well as the construction of them;
there may be other places we need to fix, although I did do a search for
the relevant types in TIKE source.