Closes: #14405
Closes: #14563

Description

This PR addresses a couple of minor changes left from previous PRs.

There is no change in behaviour. Unit tests should pass, and the POS should continue to work as it did before.

Testing information

Areas to test:
Clear button should be available when viewing the item list with something in the cart. It should not be shown when the cart is empty, or when viewing checkout.

Editing the order should work as it did before: i.e. moving to the checkout without making any changes since the last time you viewed checkout should not result in the order being updated. If you go back and make changes, the next time you tap check out the order should be re-synced.

• I have considered if this change warrants user-facing release notes and have added them to RELEASE-NOTES.txt if necessary.

Reviewer (or Author, in the case of optional code reviews):

Please make sure these conditions are met before approving the PR, or request changes if the PR needs improvement:

• The PR is small and has a clear, single focus, or a valid explanation is provided in the description. If needed, please request to split it into smaller PRs.
• Ensure Adequate Unit Test Coverage: The changes are reasonably covered by unit tests or an explanation is provided in the PR description.
• Manual Testing: The author listed all the tests they ran, including smoke tests when needed (e.g., for refactorings). The reviewer confirmed that the PR works as expected on all devices (phone/tablet) and no regressions are added.