* test(e2e): drive the real Codex CLI through the gateway and add the command round trip row
Adds tests/e2e/codex: a harness that runs codex exec --json with a throwaway HOME and CODEX_HOME, a custom responses provider pointed at the gateway, the model list read from the gateway's /v1/models, the sandbox on and approvals off. Each test registers its setup's deployment via /model/new and calls it with a key scoped to it, both deleted on teardown. The first row checks that a value only a command can print comes back through the gateway on all five setups
* test(e2e): type the Codex self-test event helper as a Mapping
* test(e2e): clean up Codex test keys even when setup fails, and fail runs where Codex exits with an error
* test(e2e): record a step when the Codex harness sets up its home and workspace
The suite rules ask every public harness helper that does something to record a step, so a failed run shows whether it died while setting up Codex or while running it
* Update run.py
wip
