Overwriting every stored snapshot with current output

Warns on a test run told to overwrite stored snapshots with whatever the code produces now: Jest's -u / --updateSnapshot, Vitest's -u / --update, Playwright's and Bun's --update-snapshots, the same flags passed through npm test, pnpm test or yarn test, pytest's --snapshot-update (syrupy and pytest-snapshot), cargo insta accept, cargo insta test --accept, and INSTA_UPDATE=always. A snapshot that no longer matches is a failing test, and accepting every difference at once makes it pass without anyone reading the diff. A warning, not a hold: regenerating snapshots after an intended change is ordinary work. Deliberately NOT matched: writing only NEW snapshots (--update=new, --update-snapshots=missing, --snapshot-update-new-only, INSTA_UPDATE=new), cargo insta review, and Jest's --ci. Misses a runner started through any other script name or wrapper, and snapshot files rewritten with a file tool. A quoted MENTION is not a use: a search, a git commit -m message, an echo or a curl --data body that only names this command is left alone. That holds only while every shell metacharacter stays inside the quotes, so git commit -m "x" && … is still caught; and the carrier must be the first word, so sudo grep … is not exempt.