fix numba stiching blend error and add numpy blend fallback

build/wheel_layout.py

@@ -83,9 +83,22 @@ def package_data_from_bundle(ext_suffix: str, items: list[dict]) -> dict[str, li
     package_data: dict[str, list[str]] = {
         "orisys": [f"*{ext_suffix}"],
         "orisys.examples": ["*.py", "README.md", "viz/**/*.py", "pipeline/**/*.py", "gui/**/*.py"],
+        "orisys_blend": ["*.py"],
     }
     for item in items:
         if item["name"] == "examples":
             continue
         package_data["orisys"].extend(package_data_paths_for_item(item))
     return package_data
+
+
+def copy_orisys_blend(repo_root: Path, wheel_root: Path) -> int:
+    """Copy pure-Python orisys_blend (Numba kernels) next to the Nuitka orisys .pyd."""
+    src = repo_root / "src" / "orisys_blend"
+    dst = wheel_root / "orisys_blend"
+    if dst.exists():
+        shutil.rmtree(dst)
+    shutil.copytree(src, dst)
+    count = sum(1 for p in dst.rglob("*.py") if p.is_file())
+    print(f"Copied orisys_blend ({count} .py files) to {dst}")
+    return count