fix(gallery): handle MPS float64 mask inputs (#5903)

Co-authored-by: Alexandre Teixeira <111787685+alteixeira20@users.noreply.github.com>

tests/test_gallery_model_input_device.py

@@ -0,0 +1,34 @@
+import routes.gallery_routes as gallery_routes
+
+
+class _TorchSentinel:
+    float32 = object()
+    float64 = object()
+
+
+class _FakeTensor:
+    def __init__(self, dtype):
+        self.dtype = dtype
+        self.to_args = None
+
+    def to(self, *args, **kwargs):
+        self.to_args = (args, kwargs)
+        return self
+
+
+def test_model_inputs_to_device_casts_mps_float64_to_float32():
+    float_tensor = _FakeTensor(_TorchSentinel.float64)
+    int_tensor = _FakeTensor("int64")
+    plain_value = object()
+
+    result = gallery_routes._model_inputs_to_device(
+        {"points": float_tensor, "labels": int_tensor, "plain": plain_value},
+        "mps",
+        _TorchSentinel,
+    )
+
+    assert result["points"] is float_tensor
+    assert float_tensor.to_args == ((), {"device": "mps", "dtype": _TorchSentinel.float32})
+    assert int_tensor.to_args == (("mps",), {})
+    assert result["plain"] is plain_value
+