Editor: user unfriendly behaviour when there are only project changes

The project changes are filtered from the synchronization when the user has Editor permission. When there are only project changes in the project, and the user hits sync, the plugin tries to synchronize. On the end, there is a "Mergin Maps project tme1/Dkrjtjng synchronized successfully" message, and in the web app, no new version of the project was created.

All of this is correct. Still, the user would see ongoing synchronization which ends in a successful message with no new version on the emerging. I believe this can be misleading. I would prefer to show the project is "Up to date" information with info that, project changes are not considered.

Also, the yellow bar on the top of the "Project status" windows disappears in case of project changes. I am not sure this is intentional.

Reproduce issue #592 in the QGIS plugin with a project containing only project changes and an Editor-permission user, then inspect the synchronization flow and Project status window. Done means the UI reports the project is up to date, explains that project changes are not considered, and confirms whether the yellow status bar should remain visible.