Add new functionality for image rectification and depth metadata handling

- Implemented a preview tool for rectifying images with interactive aspect controls in `preview.py`.
- Added tests for depth metadata loading to ensure consistent schema usage in `test_depth_metadata.py`.
- Developed comprehensive tests for cutout calibration processes in `test_cutout_calibration.py`, including stability checks and depth calibration.
- Created tests for frame compositing operations in `test_frame_compositing.py`, ensuring correct handling of depth and transparency.
- Introduced material slot inheritance functionality in `material_slots.py` to manage geometry material assignments.
- Built shared shader nodes for material processing in `shader.py`, including roughness and bump mapping setups.

tests/tools/test_docs.py

@@ -1,42 +0,0 @@
-from tests.support.paths import PROJECT_ROOT
-import importlib.util
-
-
-SCRIPT_PATH = PROJECT_ROOT / "tools" / "docs.py"
-SPEC = importlib.util.spec_from_file_location("docs_script", SCRIPT_PATH)
-docs = importlib.util.module_from_spec(SPEC)
-SPEC.loader.exec_module(docs)
-
-
-def test_documentation_command_deploys_project_version(monkeypatch):
-    monkeypatch.setattr(docs, "project_version", lambda: "1.2.3")
-
-    assert docs.documentation_command() == [
-        "mike",
-        "deploy",
-        "--update-aliases",
-        "1.2.3",
-        "latest",
-    ]
-
-
-def test_documentation_command_previews_current_source():
-    assert docs.documentation_command(dev=True) == ["mkdocs", "serve"]
-
-
-def test_main_runs_from_project_root(monkeypatch):
-    calls = []
-    monkeypatch.setattr(
-        docs.subprocess,
-        "run",
-        lambda *args, **kwargs: calls.append((args, kwargs)),
-    )
-
-    docs.main(["-dev"])
-
-    assert calls == [
-        (
-            (["mkdocs", "serve"],),
-            {"cwd": docs.PROJECT_ROOT, "check": True},
-        )
-    ]