## What happened
Exporting Flipt state fails with "wrong format for rule segments" when a variant flag has no rules attached yet. Steps: create a variant flag, do not add rules, run export. The export should succeed even for rule-less flags, since that is a normal intermediate state.
## The fix that worked
Fixed via PR #3552, which addressed the root cause of the export failure for rule-less variant flags and also improved the export error message and UI so the problem is easier to identify. Upgrade past the release containing #3552. Note the fix cannot repair database rows that are already in the inconsistent state, those need to be re-exported or recreated.