Pin NumPy to <2 to avoid NumPy 2 ABI import failures

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Motivation

• Prevent runtime import crashes caused by C-extension modules compiled against NumPy 1.x when an environment installs NumPy 2.x by bounding the project's NumPy requirement.

Description

• Change dependency in pyproject.toml from "numpy" to "numpy<2" to avoid resolving NumPy 2.x until transitive binary dependencies are confirmed compatible (file modified: pyproject.toml).

Testing

• Verified the updated dependency value with python -c "import tomllib, pathlib; data=tomllib.loads(pathlib.Path('pyproject.toml').read_text()); print(data['project']['dependencies'][0])" which printed numpy<2 (success).
• Verified package import in the current workspace with PYTHONPATH=src python -c "import cubedynamics; print('import ok')" which printed import ok (success).

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Codex Task