test(kms): move the Vault KV2 Transit-wrapping doc guard into check_fips_wording.sh
`test_vault_kv2_sources_do_not_claim_transit_wrapping` asserted that four
`include_str!`-pinned files never describe the Vault KV2 backend as wrapping key
material through Vault's Transit engine. The invariant is a documentation-claim
invariant with no behavioral twin by construction, and the test form was weak in
both directions: it saw only four files (the same prose in a fifth file passed
silently) and it stopped compiling — rather than reporting a violation — as soon
as one of them was renamed.
Move the four literals verbatim into `scripts/check_fips_wording.sh`, which
already guards the adjacent cryptographic over-claim class (unsupported FIPS
validation wording) and is anchored to the same policy document. The guard now
greps every file under `crates/kms` for the same four case-sensitive literals and
separately reports a moved pinned source instead of failing to build.
`check_fips_wording.sh` previously ran only in `make pre-commit` / `pre-pr`, so
wire it into the Quick Checks job of both CI workflows to keep the invariant's
failure visibility at least as strong as the deleted test's.
* docs(kms): record the cryptographic compliance position
RustFS links no FIPS-validated cryptographic module: the rustls provider is
the ordinary aws-lc-rs build, and every data-path AEAD is RustCrypto. The
crypto crate's default-on `fips` feature only selects PBKDF2+AES-GCM over
Argon2id, with the same RustCrypto implementations behind both branches, so
it cannot support a validation claim either.
Document that status, the terminology rules for external material, the real
semantics of the `fips` feature with a rename direction, the cost of the
three routes to a stronger position, and the sequencing rules for retiring an
algorithm.
Refs rustfs/backlog#1587 (part of rustfs/backlog#1562)
* docs(kms): document the mixed-version cluster constraints
Collect the cross-version constraints that landed with versioned rotation and
the check-and-set lifecycle work: which persisted formats decode both ways,
which guarantees only hold once every node is upgraded, how long nodes can
disagree on lifecycle state, and that reconfigure is persisted cluster-wide
but applied only on the node that handled it.
Adds the recommended rolling-upgrade sequence and the list of operations to
avoid while two builds are running.
Refs rustfs/backlog#1581 (part of rustfs/backlog#1562)