For #26178 - Adds publish_types setting to filter loader UI.

- This filters the list of publishes presented to the user when selecting publishes to be included in the new project.
That's a difficult call, especially as we don't control the style sheet for Mari.. This is just changing the default colour of the line as otherwise it is a little bright compared to the rest of the UI.  It's also unlikely that all lines will have the same colour.