Adding dlpack conversion support

Signed-off-by: Pradyot Ranjan <99216956+pradyotRanjan@users.noreply.github.com>

Author: prady0t

src/array_api_extra/_lib/_testing.py

@@ -136,6 +136,13 @@ def as_numpy_array(array: Array, *, xp: ModuleType) -> np.typing.NDArray[Any]:
         cpu = cast(Device, jax.devices("cpu")[0])
         array = to_device(array, cpu)
 
+    # Try DLPack (works for JAX and other backends)
+    if hasattr(array, "__dlpack__"):
+        try:
+            return np.from_dlpack(array)
+        except (TypeError, BufferError):
+            pass
+
     return np.asarray(array)