v0.1.2

Changes

• Added pipeline health rollups grouped by pipeline name.
• Included latest status, latest run timing, run counts, failure counts, and quality-check counts.
• Documented the new metrics endpoint and sample-data inspection flow.
• Added tests for populated and empty rollup responses.

Validation

• GitHub Actions CI passed on main.
• Local validation passed with Ruff, mypy, Alembic migration check, and pytest.