feat(node_assets): add image plane geometry nodes and validation scripts

- Implemented `image_plane.py` to build the Image Plane Geometry Nodes group with customizable parameters for geometry, subdivide, and thickness.
- Created `image_plane_validation.py` to validate the functionality of the image plane, ensuring correct geometry generation and material assignment.
- Developed `material_layers.py` to construct shader node groups for image materials, including depth and normal handling.
- Authored `plane_layouts.py` to define node arrangements for image geometry assets.
- Introduced `shadeless.py` to create a shadeless shader node group that displays color without scene lighting while preserving shadows and reflections.

tests/test_image_menu.py

@@ -0,0 +1,151 @@
+from types import SimpleNamespace
+from unittest.mock import patch
+from blender_test_support import BlenderTestCase
+
+
+class ImageMenuTest(BlenderTestCase):
+    def test_image_menu_keeps_ai_features_clickable_and_offers_models(self):
+        calls = []
+        labels = {}
+
+        class Layout:
+            operator_context = ""
+            enabled = True
+
+            def operator(self, identifier, **options):
+                calls.append((identifier, self.enabled))
+                labels[identifier] = options.get("text")
+                return SimpleNamespace()
+
+            def separator(self):
+                calls.append(("separator", self.enabled))
+
+        menu = self.anyimage.AnyImageImageMenu()
+        menu.layout = Layout()
+        with patch(
+            "anyimage.properties.ai_status",
+            return_value={
+                "environment_ready": True,
+                "missing_models": ("BEN2_BASE",),
+                "ready": False,
+            },
+        ):
+            menu.draw(
+                SimpleNamespace(
+                    object=SimpleNamespace(
+                        type="EMPTY",
+                        empty_display_type="IMAGE",
+                        data=SimpleNamespace(size=(640, 480)),
+                    )
+                )
+            )
+
+        self.assertEqual(
+            calls,
+            [
+                ("anyimage.convert_to_plane", True),
+                ("anyimage.convert_to_depth_plane", True),
+                ("separator", True),
+                ("anyimage.remove_image_background", True),
+                ("anyimage.upscale_image", True),
+                ("separator", True),
+                ("anyimage.setup_ai_environment", True),
+            ],
+        )
+        self.assertEqual(
+            labels["anyimage.setup_ai_environment"],
+            "Download Required Models…",
+        )
+
+        self.assertEqual(
+            labels["anyimage.upscale_image"],
+            "Upscale (1280 × 960)",
+        )
+
+
+    def test_image_menu_opens_environment_settings_when_ai_is_ready(self):
+        calls = []
+
+        class Layout:
+            operator_context = ""
+            enabled = True
+
+            def operator(self, identifier, **_options):
+                calls.append((identifier, self.enabled))
+                return SimpleNamespace()
+
+            def separator(self):
+                calls.append(("separator", self.enabled))
+
+        menu = self.anyimage.AnyImageImageMenu()
+        menu.layout = Layout()
+        with patch(
+            "anyimage.properties.ai_status",
+            return_value={
+                "environment_ready": True,
+                "missing_models": (),
+                "ready": True,
+            },
+        ):
+            menu.draw(None)
+
+        self.assertIn(("anyimage.open_ai_environment_settings", True), calls)
+        self.assertNotIn(("anyimage.setup_ai_environment", True), calls)
+
+
+    def test_image_edit_activation_defaults_to_frame(self):
+        calls = []
+        previous_ops = getattr(self.fake_bpy, "ops", None)
+        self.fake_bpy.ops = SimpleNamespace(
+            wm=SimpleNamespace(
+                tool_set_by_id=lambda **options: calls.append(options) or {"FINISHED"}
+            )
+        )
+        try:
+            result = self.image_frame.ActivateImageEditTool().execute(None)
+        finally:
+            if previous_ops is None:
+                del self.fake_bpy.ops
+            else:
+                self.fake_bpy.ops = previous_ops
+
+        self.assertEqual(result, {"FINISHED"})
+        self.assertEqual(
+            calls,
+            [{"name": "anyimage.frame", "space_type": "VIEW_3D"}],
+        )
+
+
+    def test_image_operators_stay_clickable_until_server_is_busy(self):
+        context = SimpleNamespace(
+            object=SimpleNamespace(data=SimpleNamespace()),
+        )
+        operators = (
+            (self.convert_to_plane, self.convert_to_plane.ConvertToDepthPlane),
+            (self.remove_background, self.remove_background.RemoveImageBackground),
+        )
+
+        for busy, expected in ((False, True), (True, False)):
+            with (
+                self.subTest(busy=busy),
+                patch.object(
+                    self.anyimage.runtime,
+                    "server_busy",
+                    return_value=busy,
+                ),
+            ):
+                for module, operator in operators:
+                    with (
+                        self.subTest(operator=operator.__name__),
+                        patch.object(
+                            module,
+                            "is_image_empty",
+                            return_value=True,
+                        ),
+                        patch.object(
+                            module,
+                            "video_total_frames",
+                            return_value=1,
+                        ),
+                    ):
+                        self.assertEqual(operator.poll(context), expected)