fix: integrate PR #3311 review feedback

- envs: rename obs keys to pixels/image, pixels/wrist_image, agent_pos
- envs: add __post_init__ for dynamic action_dim in RoboMMEEnv config
- envs: remove special-case obs conversion in utils.py (no longer needed)
- ci: add Docker Hub login, HF_USER_TOKEN guard, --env.task_ids=[0]
- scripts: extract_task_descriptions supports multiple task_ids
- docs: title to # RoboMME, add image, restructure eval section
- tests: update all key assertions to match new obs naming

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

.github/workflows/benchmark_tests.yml

@@ -332,6 +332,12 @@ jobs:
         with:
           cache-binary: false
 
+      - name: Login to Docker Hub
+        uses: docker/login-action@v3 # zizmor: ignore[unpinned-uses]
+        with:
+          username: ${{ secrets.DOCKERHUB_LEROBOT_USERNAME }}
+          password: ${{ secrets.DOCKERHUB_LEROBOT_PASSWORD }}
+
       - name: Build RoboMME benchmark image
         uses: docker/build-push-action@v6 # zizmor: ignore[unpinned-uses]
         with:
@@ -342,6 +348,7 @@ jobs:
           tags: lerobot-benchmark-robomme:ci
 
       - name: Run RoboMME smoke eval (1 episode)
+        if: env.HF_USER_TOKEN != ''
         run: |
           docker run --name robomme-eval --gpus all \
             --shm-size=4g \
@@ -356,6 +363,7 @@ jobs:
                 --env.type=robomme \
                 --env.task=PickXtimes,BinFill,StopCube,MoveCube,InsertPeg \
                 --env.dataset_split=test \
+                --env.task_ids=[0] \
                 --eval.batch_size=1 \
                 --eval.n_episodes=1 \
                 --eval.use_async_envs=false \