**Related issue:** Resolves#46235
# Checklist for submitter
If some of the following don't apply, delete the relevant line.
- [x] Changes file added for user-visible changes in `changes/`,
`orbit/changes/` or `ee/fleetd-chrome/changes`.
See [Changes
files](https://github.com/fleetdm/fleet/blob/main/docs/Contributing/guides/committing-changes.md#changes-files)
for more information.
## Testing
- [x] Added/updated automated tests
- [ ] QA'd all new/changed functionality manually: Pending if possible
<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit
* **Bug Fixes**
* Fixed DEP sync so progress is only saved after device data is written
successfully, preventing missed enrollment events during interrupted
syncs.
* Improved handling of sync errors so the next run can safely replay
affected devices instead of skipping them.
* Added end-to-end and scenario coverage to verify cursor behavior after
successful syncs, errors, and expired cursors.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
Andrew Mellor
2abc49ba02