[TATP-233]

Summary

• Deleted tests/base/test_sim_backend.py, the stale 158-case UniLab full-matrix mirror that still invoked removed SimBackend host/NumPy APIs (set_state, step, get_base_pos, host DOF/body/sensor getters).
• Deleted tests/base/test_genesis_runtime.py, the duplicate Genesis real-runtime acceptance lane now owned by unisim adapter/real-CUDA coverage.
• Kept UniLab's thin public backend contract/integration coverage (test_backend_conformance.py, test_sim_backend_smoke.py, architecture boundary, timing, and Genesis fake-runtime integration).
• Updated the English and Chinese backend-contract/new-backend docs and stale test comments to point to the retained tensor-contract entrypoints.
• No runtime or public-contract change; no legacy host backend API was restored.

Linked Work

• Issue: tests/base/test_sim_backend.py 慢车道大面积失败：host API 漂移（set_state/get_base_pos/step 已移除） #2430
• Parent roadmap: none
• Roadmap declared base: none
• Milestone: none
• Base branch: main
• Contract: ADR-0012 Sole Tensor Manager And Scoped Backends

Validation

• make test-all passed on the final local head before this PR was created or updated
• Additional task-specific validation listed below

Commands actually run:

uv run pytest -q \
  tests/architecture/test_backend_public_contract_boundary.py \
  tests/base/test_backend_conformance.py \
  tests/base/test_sim_backend_smoke.py \
  tests/base/test_sim_backend_set_state_timing.py \
  tests/base/test_genesis_backend.py
# 59 passed, 20 skipped, 23 deselected

uv run pytest tests/scripts/test_check_docs.py -q
# 20 passed

cd docs/sphinx
UNILAB_DOCS_SKIP_AUTODEC=1 uv run --no-project --with-requirements requirements.txt \
  sphinx-build -b html -n source build/html
# build succeeded, 242 warnings (pre-existing autodoc/unisim reference warnings; not introduced here)

make check
# passed

make test
# 2678 passed, 60 skipped, 362 deselected

make test-all
# check passed; 2678 passed, 60 skipped, 362 deselected; benchmark smoke module 34/34 and script 35/35

rg -n \
  "tests/base/test_sim_backend\.py|tests/base/test_genesis_runtime\.py|test_sim_backend\.py|test_genesis_runtime\.py" \
  . --glob '!*.lock' --glob '!CHANGELOG*' --glob '!*.bak'
# no active entrypoint references

git diff --check
# clean

Remote CI route:

• Base main: CI run 39268798359 for head 43b292f passed all jobs (test, benchmark-smoke, ruff-format, ruff-lint, mypy, pyright).

Impact

• Backend impact: none
• Platform impact: none
• Training effect expected: no

Artifacts

• W&B: none
• benchmark result: none
• video / screenshot: none
• ONNX / checkpoint: none

Checklist

• Added or updated tests where needed
• Updated docs if behavior or workflow changed
• Linked the driving issue
• Noted any follow-up work explicitly