This is a PR to keep them relatively small. Very likely changes, validations and other features will be added.
What:
Basic methods to cancel, confirm or decline order changes
Apply order changes to modify and create a new version of an order
Things related to calculation, Order and Item totals are not covered in this PR. Properties won't match with definition, etc.
Co-authored-by: Adrien de Peretti <25098370+adrien2p@users.noreply.github.com>