Add provisioning/config.py with read/write/wipe functions, update
conftest.py with autouse CONFIG_PATH patch fixture, write 7 tests
covering all acceptance criteria, and extend pyproject.toml
per-file-ignores so conftest.py may import from provisioning.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Creates the complete src/planemapper/ layout with all module stubs,
provisioning and renderer subpackages, airports.csv data bundle,
systemd unit files, and full test scaffold. All three quality gates
pass: pytest 12/12, ruff check zero violations, ruff format clean.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>