fix(tree): prevent revert of commits that were rolled back

[yann-achard-MS]

Description

A commit can be rolled back through SharedTreeCore.rollback. Once that is done, the revertible for that commits become invalid. Before this PR, we allowed applications to attempt a revert, which could either crash or perform undesirable edits. This PR ensures that the relevant revertible is disposed.

Breaking Changes

None

[github-actions]

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[Copilot]

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.