PiperOrigin-RevId: 848316991 Change-Id: Idbf7ba81b4da711a22c23302c8782ab2b0b98d82
Move row-flipping logic from `mjCModel::CopyBack` to `mjXWriter`. PiperOrigin-RevId: 842220322 Change-Id: I6fb09db6c9e8689f6e435f82f58dd3e7c4314478