Refactor Python package metadata

[Callum027]

• Replace Poetry with PDM.
• Rewrite pyproject.toml to make it fully PEP-621 compliant, with some PDM options defined such as development dependencies.
• Switch to dynamic version management using setuptools-scm.
• Replace Black with the Ruff formatter.
• Update Ruff configuration to take into account option changes.
• Rewrite GitHub Actions workflows to use PDM.
• Switch the release workflow to getting the PyPI token using GItHub Actions OIDC, instead of passing it in as a repository secret.
• Publish the source dist and wheels to the GitHub release.
• Include non-functional changes resulting from the changed pre-commit hooks.