Align CPS health coverage anchors with at-interview rule inputs

[daphnehanse11]

Closes #629

Summary

• import CPS NOW_* current-coverage flags as reported health coverage fields and emit the corresponding has_*_health_coverage_at_interview rule inputs needed by policyengine-us
• keep compatibility aliases for existing Marketplace and ESI inputs while adding current-coverage detail used for ACA and Medicaid reconciliation
• anchor ACA takeup to tax-unit-level reports of reported_has_subsidized_marketplace_health_coverage_at_interview, while anchoring Medicaid takeup to has_medicaid_health_coverage_at_interview, in CPS construction, local-area publishing, and unified calibration
• add regression coverage that keeps unsubsidized Marketplace coverage separate from the ACA takeup anchor

Testing

• uv run pytest tests/unit/test_stochastic_variables.py tests/unit/calibration/test_unified_calibration.py tests/integration/test_cps.py::test_add_personal_variables_maps_current_health_coverage_flags -q
• uv run make format