chore(project): add python package foundation

[jaeyeopme]

Motivation

Add the package foundation needed before implementing the export workflow.

Scope

• Add Python package tooling with uv, Hatchling, pytest, ruff, coverage, and basedpyright.
• Add the typed package shell and workflow contract models.
• Add a minimal Typer command shell so the configured console script is not broken.
• Add CI for Python 3.11 and 3.13.

Out of Scope

• Source fixture behavior.
• Mapping, validation, and duplicate handling rules.
• FastAPI export endpoint.
• Real export CLI command.
• Source data or output files.
• Public docs status changes.

Modifications

• Introduce src/clean_data_export_api with config defaults, typed models, py.typed, and CLI help.
• Add tests for config defaults, date range validation, rejected reason codes, model contracts, and CLI help.
• Add locked dependencies and CI checks for tests, ruff, basedpyright, and coverage.

Test Plan

• uv sync
• uv sync --locked
• uv run pytest tests/test_config.py tests/test_models.py tests/test_cli.py -v
• uv run ruff check src tests
• uv run basedpyright
• uv run pytest tests/test_config.py tests/test_models.py tests/test_cli.py --cov=clean_data_export_api --cov-report=term-missing --cov-fail-under=90
• uv run python -m compileall src tests
• uv run clean-data-export-api --help

Docs Impact

none

ADR Check

• No architecture or scope decision needs a new or updated ADR.

Result

The repo can install, expose typed workflow contracts, run the CLI help surface, and verify package foundation checks in CI without export workflow behavior.