Replay previously matched interactions by transport verb and path in
recorded order, so a request whose body drifted from the recording
silently replayed the stale response, and reordering two independent
calls broke replay even though both were recorded. Match keys are now
canonical: fixture_canonical.py strips volatile headers and credential
fields, replaces unique markers, generated ids, uuids, and timestamps
with fixed placeholders, sorts object keys, and hashes what remains, so
a key is stable across runs and machines while any real content drift
is a hard ReplayMiss naming the computed key, the closest recorded key
with its file, and a content diff, with no fallthrough to a live call.
Matching is order-independent across distinct keys and FIFO within one
key. Recording now also redacts credential body and form fields (not
just auth headers) so provider keys never land in bundles.
Resolves LIT-5741
E2E_FIXTURE_MODE selects the transport every e2e client is built on: live
(default, unchanged behavior), record (pass through to the live proxy while
writing every interaction to a fixture bundle), or replay (serve every
interaction from the bundle with no proxy and no provider spend). Both new
transports fulfil the existing Transport protocol, so no test changes shape.
A bundle is a directory with a manifest (record timestamp, harness version,
format version) and one JSON file per interaction, grouped per test in call
order. Replay against a manifest older than seven days hard-fails at
collection time naming the bundle age. Record always wipes and never reads
the previous bundle, refusing to wipe a directory that is not a bundle.
Auth header values are redacted on write; uploads store a sha256 digest.
unique_marker() becomes deterministic per test in record/replay modes so a
replay run regenerates exactly the requests the record run sent.
Content-based match keys, streaming chunk fidelity, and provider-scoping are
follow-ups (LIT-5741, LIT-5742, LIT-5745).
