test(e2e): add the outbound target matrix and the replication checksum postmortem
Defense work for rustfs#7082, the regression rustfs#6895 introduced while
fixing rustfs#6853: a fix for one target class changed a client default for
every target class and nothing in tree modeled the other classes.
- docs/postmortems: timeline, root cause, why four defense layers missed
it, and the SOP for changing any outbound client default; AGENTS.md and
the adversarial compatibility lens point at it; the two env knobs from
rustfs#6895 are documented in docs/operations.
- fake_s3_target: reject_aws_chunked_uploads, require_checksum_for_object_lock
(Content-MD5 always verified), create_bucket_with_object_lock with a
GetObjectLockConfiguration handler, and a TransportSnapshot on every
journal record.
- replication_target_matrix_test: six object shapes against four target
modes with an explicit expectation table; the two rustfs#7082 cells are
pinned KnownFailing and fail with an XPASS message once the fix lands.
Wired into e2e-repl-nightly, excluded from e2e-full.
唐小鸭