Fix Render Server Crash: Switch back to egl with llvmpipe headless fallback

Dockerfile

@@ -35,8 +35,8 @@ RUN git clone --depth 1 --filter=blob:none --sparse https://github.com/google-de
     && rm -rf .git
 
 # ── MuJoCo environment ────────────────────────────────────────────────────────
-ENV MUJOCO_GL=osmesa
-ENV PYOPENGL_PLATFORM=osmesa
+ENV MUJOCO_GL=egl
+ENV PYOPENGL_PLATFORM=egl
 
 # ── Expose port ───────────────────────────────────────────────────────────────
 EXPOSE 8000

SemSorter/server/agent_bridge.py

@@ -160,7 +160,7 @@ def get_simulation():
     global _sim
     with _sim_lock:
         if _sim is None:
-            os.environ.setdefault("MUJOCO_GL", "osmesa")
+            os.environ.setdefault("MUJOCO_GL", "egl")
             from controller import SemSorterSimulation
             logger.info("Initialising MuJoCo simulation…")
             _sim = SemSorterSimulation()