Refactor geometry generation to standardize Blender object coordinates

- Unified the canonical local frame for generated geometries (Plane, Depth Plane, Relief Plane, Cutout, Depth Cutout) to align with Blender's object coordinate system, setting X as horizontal, Z as up, and +Y as depth.
- Removed the `Depth Axis` parameter from `O Image Cutout` and `O Image Depth Cutout`, simplifying the geometry generation process.
- Updated the depth direction defaults to use +Y instead of -Z for `O Image Relief Plane` and Depth Symmetry.
- Adjusted the geometry nodes to ensure thickness, projection, and shell displacements operate along the Y-axis.
- Implemented new capabilities for handling object space normals to align with the new canonical frame.
- Enhanced the Depth Symmetry functionality to mirror across the canonical Y-axis and perform a final rotation to maintain the correct orientation.
- Added tests to validate the new coordinate system and ensure compatibility with existing assets.

tests/anyimage/operators/test_cutout_edge_length.py

@@ -48,7 +48,7 @@ def test_mesh_density_survives_resolution_and_canvas_changes(fine_outline):
     assert max(counts) / min(counts) < 1.05
     for mesh in meshes:
         assert np.isfinite(mesh.vertices).all()
-        np.testing.assert_allclose(np.ptp(mesh.vertices[:, :2], axis=0), (1, 1), atol=0.03)
+        np.testing.assert_allclose(np.ptp(mesh.vertices[:, [0, 2]], axis=0), (1, 1), atol=0.03)
 
 
 @pytest.mark.parametrize("fine_outline", (False, True))
@@ -60,7 +60,7 @@ def test_world_scaling_adds_samples_and_rotation_preserves_density(fine_outline)
         source = source_plane(matrix=matrix)
         mesh = g.build_base_shape(bpy.context, source, 0.1, alpha, (0, 0, 100, 100), fine_outline=fine_outline)
         counts.append(len(mesh.vertices))
-        planar = mesh.vertices[:, :2] @ g.metric_transform(g.world_plane_metric(matrix)[0])
+        planar = mesh.vertices[:, [0, 2]] @ g.metric_transform(g.world_plane_metric(matrix)[0])
         edges = np.unique(np.sort(np.concatenate([mesh.faces[:, [0, 1]], mesh.faces[:, [1, 2]], mesh.faces[:, [2, 0]]]), axis=1), axis=0)
         lengths = np.linalg.norm(planar[edges[:, 0]] - planar[edges[:, 1]], axis=1)
         assert 0.06 < np.median(lengths) < 0.14