Refactor tests and remove unused imports

- Cleaned up test files by removing unnecessary imports and unused parameters.
- Simplified test functions by eliminating redundant parameterization and consolidating logic.
- Updated test cases to directly use defined values instead of parameterized inputs where applicable.
- Enhanced readability and maintainability of the test code across various test files.

tests/tools/nodes/test_boundary_smoothing.py

@@ -177,9 +177,8 @@ def test_cutout_boundary_smooth_defaults_to_four():
     assert (socket.min_value, socket.max_value) == (0, 16)
 
 
-@pytest.mark.parametrize("triangles", [False, True])
-def test_smoothing_reduces_stairs_without_leaving_two_ring_band(triangles):
-    obj, set_value = diagonal_surface(triangles)
+def test_smoothing_reduces_stairs_without_leaving_two_ring_band():
+    obj, set_value = diagonal_surface(triangles=True)
     original, faces = evaluated(obj)
     boundary = boundary_neighbors(faces)
     outer = np.isclose(original[:, 0], 0) | np.isclose(original[:, 0], 2)
@@ -223,8 +222,8 @@ def test_smoothing_without_split_moves_outline_only_within_boundary_band():
     np.testing.assert_array_equal(evaluated(obj)[0], original)
 
 
-@pytest.mark.parametrize("mode", [0, 1])
-def test_smoothed_cut_shells_stay_closed_and_separate(mode):
+def test_smoothed_cut_shells_stay_closed_and_separate():
+    mode = 1
     from anyimage.common.object import modifier_input_identifier, set_modifier_input
 
     obj, set_value = diagonal_surface(triangles=True)