Add tests for image layer, image plane, inventory, saved layout, commands, documentation, manifest, and packaging

- Implement tests for image layer functionality including alpha curve and depth layer behavior.
- Create tests for image plane evaluation and modifier input handling.
- Add tests to verify the saved asset inventory and its persistence.
- Introduce tests for the documentation command to ensure correct project version deployment.
- Validate the extension manifest structure and required permissions.
- Develop tests for the packaging process, ensuring correct platform handling and dependency management.
- Enhance image depth plane group functionality with new split threshold input and surface processing.

tests/anyimage/common/test_node_loading.py

@@ -0,0 +1,14 @@
+from tests.support.paths import PROJECT_ROOT
+import unittest
+from tests.anyimage.common.support import load_common_modules
+
+class NodeLoadingTest(unittest.TestCase):
+    @classmethod
+    def setUpClass(cls):
+        cls.modules = load_common_modules()
+
+    def test_node_asset_path_resolves_bundled_library(self):
+        self.assertEqual(
+            self.modules.node.node_asset_path(),
+            PROJECT_ROOT / "src" / "anyimage" / "assets" / "O_AnyImage.blend",
+        )