Ensure cursor is restored to step after refreshing annotations

Clearing and then drawing the annotations may cause the cursor to end up in a non-step position.

This bug is not currently reproducible in the demo editor, as it relies on the ``OdtDocument.cloneDocumentElement`` function being called, something which is currently only done by the TrivialUndoManager to save the initial document state. Bella does do this somewhat regularly during fuzzing however.