Add to data/talkactions/talkactions.xml:

<talkaction words="!shop" script="znoteshop.lua"/>

Then put znoteshop.lua in data/talkactions/scripts/ and restart the server.

OTHire (7.72) has no mounts or addons, so only shop order types 1 (items) and
5 (outfit look type) are delivered in game. Everything else is handled by the
website.