fix: bump gradio to 5.x to resolve websockets<13 vs openenv-core>=15 conflict

space/env/requirements.txt

@@ -4,4 +4,8 @@ pydantic>=2.0.0
 fastapi>=0.110.0
 uvicorn>=0.27.0
 openenv-core[core]>=0.2.3
-gradio>=4.40.0,<5.0
+# gradio>=4.40 was the original target; bumped to 5.x because
+# openenv-core 0.2.3 requires websockets>=15.0.1, while gradio 4.x
+# pulls gradio-client 1.2 which caps websockets<13. gradio 5.x's
+# gradio-client raised that ceiling, resolving the conflict.
+gradio>=5.0,<6.0