BRANCH REBASER / Clean up history before the PR

Your feature branch is a mess. Drop the junk commit and reorder the rest into a clean, reviewable history.

▸ git rebase -i — oldest commit on top. Reorder with the arrows and drop anything that shouldn't ship.

b27e41test: cover checkout endpoint

c8d3aawip: asdfasdf debug console.log

e91c55docs: document checkout API

d40b17fix: handle empty cart

a1c9f0feat: add checkout endpoint