Prove (or disprove) that a terraform change was actually applied to an environment,
without trusting a PR description or a human's memory. Use when: (1) someone asks
"did we test/apply this on dev?" and the only evidence is prose in a PR body,
(2) you need to know WHICH variant of a change was applied and in what order
(e.g. a stacked PR pair applied separately vs. all at once), (3) live AWS shows
resources that a teardown was supposed to delete and you must tell "apply never ran"
apart from "resource was never terraform-managed", (4) you suspect a manual env apply
was later reverted or overwritten by a CI apply. Method: census the versioned S3
tfstate objects over time (…
