admin-commands: move the chainsaw extension to the admin commands module Activating an extension is always a little bit of a chore and the long name, options and "chainsaw" bits are deterrent enough. This also allows us to help the discoverability for people looking for repo "administration" tools, with the widest semantic of "administration".

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    "conduit_uri": "https://phab.mercurial-scm.org/api",
    "phabricator.uri": "https://phab.mercurial-scm.org/",
    "repository.callsign": "HG",
    "arc.land.onto.default": "@",
    "base": "hg:.^"
}