refactor(mediapipe): simplify GPU delegate preference logic and remove unused CUDA visibility check

src/pozify/steps/pose_backends/mediapipe.py

@@ -117,7 +117,7 @@ class _MediaPipeTasksPoseAdapter:
             return gpu_delegate
         if configured_delegate not in {"", "auto"}:
             return self._cpu_delegate()
-        if zero_gpu_enabled() or _cuda_device_visible():
+        if zero_gpu_enabled():
             return gpu_delegate
         return self._cpu_delegate()
 
@@ -195,22 +195,6 @@ def _create_legacy_pose(mediapipe_module: Any) -> Any:
         raise _native_library_error(exc) from exc
 
 
-def _cuda_device_visible() -> bool:
-    for env_name in ("CUDA_VISIBLE_DEVICES", "NVIDIA_VISIBLE_DEVICES"):
-        value = os.getenv(env_name)
-        if value and value.strip().lower() not in {"", "-1", "none", "void", "no"}:
-            return True
-
-    try:
-        import torch
-    except Exception:
-        return False
-
-    cuda = getattr(torch, "cuda", None)
-    is_available = getattr(cuda, "is_available", None)
-    return bool(callable(is_available) and is_available())
-
-
 def _native_library_error(exc: OSError) -> PoseBackendUnavailableError:
     return PoseBackendUnavailableError(
         "MediaPipe could not load native system libraries. On Hugging Face Spaces, "

tests/test_pose_steps.py

@@ -325,12 +325,6 @@ class MediaPipeTasksDelegateTests(unittest.TestCase):
         with patch.dict(os.environ, {"SPACES_ZERO_GPU": "1"}, clear=True):
             self.assertEqual(adapter._preferred_delegate(), "gpu")
 
-    def test_mediapipe_tasks_prefers_gpu_when_cuda_device_is_visible(self) -> None:
-        adapter = self._adapter(self._fake_mediapipe())
-
-        with patch.dict(os.environ, {"CUDA_VISIBLE_DEVICES": "0"}, clear=True):
-            self.assertEqual(adapter._preferred_delegate(), "gpu")
-
     def test_mediapipe_delegate_env_can_force_gpu(self) -> None:
         adapter = self._adapter(self._fake_mediapipe())