CreateAccessPolicy treated a Cloudflare "policy_already_exists" as idempotent
success and kept whatever policy was there. On a re-run with a changed
identity — or against a hand-made broader policy — op.console would stay
guarded by something weaker than the fail-closed body this package builds and
guards, while Setup reported success. The fail-closed validation only ever ran
on the policy we built, never on the one that stayed live.
Now it upserts by name: lookup, PUT the guarded body over the existing policy,
POST only when absent (a racing POST re-looks up and PUTs). apiPost/apiPut
share one apiWrite; three httptest cases pin update-over-existing, create-when-
absent, and the race fallback.
Lemon-miaow