Increase coverage threshold to 99% and update CLI test annotation

Fixed in setup.py:53:

• Editable builds now use in-tree native artifacts.
• Redundant second native build removed.
• Normal wheel destination is created explicitly.
• Added packaging regression tests.
• Corrected installation documentation.

Use:

pip install --upgrade numpy setuptools wheel pip install --no-build-isolation -e '.[test]'

Verification passed: editable wheel, native wheel/Twine, Ruff/YAPF, and 1,929 tests with 99.54% coverage.