[Subtask] Define rolling-upgrade compatibility for version-CAS OCC

### Describe the subtask

Version-CAS OCC introduces conditional updates and version increments that may differ between old and new servers during a rolling upgrade. Define the compatibility strategy, rollout order, downgrade behavior, feature gating, and mixed-version alter/drop tests to prevent lost updates.

### Parent issue

https://github.com/apache/gravitino/issues/12166

Start with the parent issue #12166 and the version-CAS OCC design described here. Define the rollout order, downgrade behavior, feature gating, and mixed-version alter/drop tests, with compatibility between old and new servers and prevention of lost updates as the completion criteria.

Written by the indexing model from the issue text.