* test(e2e): move the harness self-tests out of tests/e2e
The nightly Buildkite run copies tests/e2e into the runner image and runs
bare pytest, so the 672 tests of the harness itself (fixture parsing, JUnit
properties, the stack lock, the load aggregators, the Claude Code driver)
counted as e2e tests on the status page even though none of them reaches a
proxy. They now live in tests/e2e_harness, mirroring the tests/e2e layout,
and run in the GitHub Actions lint job and the CircleCI
provider_replay_harness job instead
* fix(ci): point the providers replay controls at tests/e2e_harness
The providers integration job still selected the four replay-control
tests under tests/e2e/test_provider_edge.py, so pytest exited before
they ran. The raw-HTTP check's file walk also drops to one loop per
comprehension
* style(tests): mark the raw-HTTP check's bindings Final
Replaces the test-side fixture transport with an in-process provider-edge
HTTP server the proxy's deployments point their api_base at. Record forwards
provider calls verbatim and writes them to the bundle; replay answers them
from the bundle with zero provider calls while key auth, routing, cost
calculation, and spend-log writes still execute against the live proxy and
database. Drift comes back as HTTP 599 naming the computed and closest
recorded keys. Request headers are never stored and responses are kept
byte-identical between modes from the proxy's side of the socket.
