mergin push prints "Done" and exits 0 when changes remain beyond MAX_UPLOAD_CHANGES #328

With more than 100 local changes, mergin push uploads one batch, prints Done and exits 0. LocalProjectChanges truncates the batch to MAX_UPLOAD_CHANGES, taking additions first. The changes left over show up only in a later mergin status.

Seen in 0.14.2. push() in cli.py and the limit are unchanged in 0.15.0.

To reproduce

1. Add 150 files to a project.
2. Run mergin push. It prints Done.
3. Run mergin status. It still lists 50 additions.

A script that checks the exit code reads this as a complete push. We pushed two projects of about 965 changes each, and each push moved exactly 100. Looping push until status was empty finished them, which is what mergin sync does internally.

Could push either keep going like sync, or say how many changes remain and exit non-zero?