The publisher application serves and renders items published by Camlistore. That is, items that are children, through a (direct or not) camliPath relation, of a camliRoot node (a permanode with a camliRoot attribute set).
#fileembed pattern .+\.(js|css|html|png|svg|js.map)$
The publisher command is a server application to publish items from a Camlistore server. See also https://camlistore.org/doc/publishing