Add WS2 smoke test to the existing system-test harness

[FloareDor]

This adds the WS2 Office/Kim smoke as a normal pytest mark in the existing system-test harness.

There is no new GitHub workflow. The existing System Tests job keeps ownership of the OSMO runner, AirStack images, Python setup, logs, and artifacts. When ws2_smoke is selected, it only adds the WS2-specific setup: the pinned Collision-avoidance repo/model, mononav_bridge build, and the short validate_timeout episode.

Run it from an upstream branch with:

/pytest -m ws2_smoke

or choose System Tests in Actions and set marks to ws2_smoke.

Validation:

• 43 existing WS2 bench tests pass under Ubuntu 22.04
• the new GPU test stays skipped unless the workflow finishes its WS2 setup
• workflow YAML and git diff checks pass

[FloareDor]

Maintainer handoff:

This workflow passed all 46 Linux unit/contract tests locally. Because this PR originates from a fork, GitHub correctly will not execute its code on the lab self-hosted/OSMO runner.

Could someone with castacks/AirStack write access copy commit 6400ab5 onto an upstream test branch, then manually dispatch System Tests on that branch with:

• ws2_smoke=true
• ws2_rebuild_airstack_images=false
• the default ws2_office_usd value

If the first run reports missing Docker images, please rerun with ws2_rebuild_airstack_images=true.

The run should upload a ws2-office-smoke-* artifact containing result.json, logs, provenance, episode stdout, and ci-summary.md. After it passes, this PR can be merged into eungchang/adv-ws2.

[FloareDor]

Update: I simplified this to reuse the existing system-test/OSMO harness. The earlier ws2_smoke=true instructions are obsolete. After copying the latest branch to an upstream branch, run /pytest -m ws2_smoke (or set the System Tests marks field to ws2_smoke).

[FloareDor]

Closing this. We’ll use the existing OSMO setup for the one-off WS2 smoke instead of adding a permanent CI path.