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/tools/nodes/test_cli.py

@@ -0,0 +1,88 @@
+from tests.support.paths import PROJECT_ROOT
+import importlib.util
+from unittest.mock import patch
+import pytest
+
+
+SCRIPT_PATH = PROJECT_ROOT / "tools" / "nodes" / "cli.py"
+
+
+def load_launcher():
+    specification = importlib.util.spec_from_file_location(
+        "node_asset_launcher",
+        SCRIPT_PATH,
+    )
+    module = importlib.util.module_from_spec(specification)
+    specification.loader.exec_module(module)
+    return module
+
+
+def test_blender_path_prefers_explicit_path(tmp_path):
+    launcher = load_launcher()
+    executable = tmp_path / "blender"
+    executable.touch()
+
+    with patch.dict("os.environ", {"BLENDER_BIN": "ignored"}):
+        assert launcher.blender_path(executable) == executable
+
+
+def test_blender_path_reads_environment(tmp_path):
+    launcher = load_launcher()
+    executable = tmp_path / "blender"
+    executable.touch()
+
+    with patch.dict("os.environ", {"BLENDER_BIN": str(executable)}):
+        assert launcher.blender_path() == executable
+
+
+def test_blender_path_reads_project_dotenv(tmp_path):
+    launcher = load_launcher()
+    executable = tmp_path / "Blender 4.5" / "blender.exe"
+    executable.parent.mkdir()
+    executable.touch()
+    env_path = tmp_path / ".env"
+    env_path.write_text(
+        f'BLENDER_BIN="{executable}"\n',
+        encoding="utf-8",
+    )
+
+    with patch.dict("os.environ", {}, clear=True), patch.object(
+        launcher,
+        "PROJECT_ROOT",
+        tmp_path,
+    ):
+        assert launcher.blender_path() == executable
+
+
+def test_blender_path_reports_missing_configuration(tmp_path):
+    launcher = load_launcher()
+
+    with patch.dict("os.environ", {}, clear=True), patch.object(
+        launcher.shutil,
+        "which",
+        return_value=None,
+    ), patch.object(
+        launcher,
+        "PROJECT_ROOT",
+        tmp_path,
+    ):
+        with pytest.raises(RuntimeError, match="Blender not found"):
+            launcher.blender_path()
+
+
+def test_launcher_runs_asset_build_and_validations_before_tests(monkeypatch, tmp_path):
+    launcher = load_launcher()
+    executable = tmp_path / "blender"
+    executable.touch()
+    calls = []
+    monkeypatch.setattr(launcher, "blender_path", lambda _: executable)
+    monkeypatch.setattr(launcher, "run", calls.append)
+    monkeypatch.setattr("sys.argv", ["build_nodes"])
+
+    launcher.main()
+
+    assert len(calls) == 3
+    assert "runpy.run_module('tools.nodes.build', run_name='__main__')" in calls[0][-1]
+    assert "runpy.run_module('tools.nodes.check', run_name='__main__')" in calls[1][-1]
+    assert all(command[1:6] == ("--factory-startup", "--background", "--python-exit-code", "1", "--python-expr") for command in calls[:-1])
+    assert calls[-1][1:] == ("-m", "pytest")