fix: rename [sim] extra to [sim-mujoco] per review

Address yinsong1986's feedback to namespace the optional dependency
group as [sim-mujoco] for clarity when additional sim backends are added.

Author: strands-agent

pyproject.toml

@@ -48,13 +48,13 @@ groot-service = [
 lerobot = [
     "lerobot>=0.5.0,<0.6.0",
 ]
-sim = [
+sim-mujoco = [
     "mujoco>=3.0.0,<4.0.0",
 ]
 all = [
     "strands-robots[groot-service]",
     "strands-robots[lerobot]",
-    "strands-robots[sim]",
+    "strands-robots[sim-mujoco]",
 ]
 dev = [
     "pytest>=6.0,<9.0.0",

strands_robots/simulation/mujoco/simulation.py

@@ -295,7 +295,7 @@ def _ensure_meshes(model_path: str, robot_name: str):
                     {
                         "text": (
                             f"❌ Auto-download failed for '{robot_name}': {e}. "
-                            f"Install robot_descriptions: pip install strands-robots[sim]"
+                            f"Install robot_descriptions: pip install strands-robots[sim-mujoco]"
                         )
                     }
                 ],

strands_robots/tools/download_assets.py

@@ -7,7 +7,7 @@
 Assets are cached in ``~/.strands_robots/assets/`` (override with
 ``STRANDS_ASSETS_DIR``).  Install the optional dependency::
 
-    pip install strands-robots[sim]   # includes robot_descriptions
+    pip install strands-robots[sim-mujoco]   # includes robot_descriptions
 
 CLI::