hgrc: search XDG_CONFIG_HOME on mac Searching for hgrc was special cased not to look through ~/.config/hg on Mac, but that’s unnecessary: Macs support it as do other unix based systems. There are plenty tools that use it there, e.g. git, and people expect it to work, e.g. "https://stackoverflow.com/questions/72499837/mercurial-on-macos-doesnt-read-config-hg-hgrc". Initial code introduced in 354020079723.

base-revsets: use an author that actually exercises a lot of changesets This was caught in my big find-and-replace: d4ba4d51f85f. The point of `base-revsets` is to give revsets that will give a good coverage of the repository. Using Pierre-Yves as the second largest committer (in terms of number of changesets) seems like a good idea.

match: simplify the rust-side file pattern kind parsing There's no need to add the ':' characters if we're simply pattern matching against constants next.