docs: add CLAUDE.md detailing build, test, style, and project conventions for apcore-cli-python.

Author: tercel

CLAUDE.md

@@ -0,0 +1,30 @@
+# CLAUDE.md — apcore-cli-python
+
+## Build & Test
+
+- `pytest` — run all tests. **Must pass before considering any task complete.**
+- `pytest --cov` — run with coverage report.
+- `ruff check .` — lint check.
+- `ruff format .` — format all code. **Run after every code change.**
+
+## Code Style
+
+- Python 3.11+ with `from __future__ import annotations`.
+- All code must pass `ruff check` and `ruff format --check`.
+- Type annotations on all public function signatures.
+- Use `click.echo()` for user-facing output, `logger.*` for debug/diagnostic output.
+- Prefer `sys.exit(code)` with exit code constants over raising exceptions for CLI errors.
+
+## Project Conventions
+
+- Spec repo (single source of truth): `../apcore-cli/docs/`
+- Package structure: `src/apcore_cli/` with `__init__.py` exporting `__version__` only.
+- Entry point: `apcore_cli.__main__:main`.
+- Security modules live in `src/apcore_cli/security/` sub-package.
+- ConfigResolver.DEFAULTS values are Python-typed (str, int, bool).
+- Tests organized by module: `tests/test_<module>.py`, security tests in `tests/test_security/`.
+
+## Environment
+
+- Python >= 3.11
+- Key dependencies: click >= 8.0, rich >= 13.0, jsonschema >= 4.0, pyyaml >= 6.0