Global Configuration Selection Dialog
One answer
Found the picker dialog description. It's in a generic service provider URL not the URL for a specific project area.
https://<server>:9443/gc/rootservices
<global_config:globalConfigServiceProviders rdf:resource="https://<server>:9443/gc/oslc-config/catalog"/>
https://<server>:9443/gc/oslc-config/catalog
(will list a service provider for each project area followed by a generic entry and this entry will contain the description of the picker dialog)
<oslc:serviceProvider rdf:resource="https://<server>:9443/gc/oslc-config/serviceProvider/_WZfNsNsyEeqbLuH9n7-FrQ"/>
<oslc:serviceProvider rdf:resource="https://<server>:9443/gc/oslc-config/serviceProvider/_CjL8oNNmEeqrZqF4KvMwVw"/>
<oslc:serviceProvider rdf:resource="https://<server>:9443/gc/oslc-config/serviceProvider"/>
https://<server>:9443/gc/oslc-config/serviceProvider
<oslc:dialog rdf:resource="https://<server>:9443/gc/configurationPicker"/>