Add Medicaid CE SNAP/TANF pass-through

[daphnehanse11]

Summary

Fixes #8267 by adding a Medicaid community engagement pass-through for SNAP and TANF work-compliance determinations.

Regulatory Authority

• H.R. 1, 119th Congress, section 71119, adding Social Security Act section 1902(xx).
• CMS CMCS Informational Bulletin, December 8, 2025: https://www.medicaid.gov/federal-policy-guidance/downloads/cib12082025.pdf#page=6

Implementation

• Adds medicaid_community_engagement_pass_through_eligible, a monthly person-level Medicaid CE primitive.
• Uses person-level SNAP work primitives instead of the household-wide meets_snap_work_requirements output, avoiding the issue SNAP work requirements applied as household-wide disqualification instead of per-person exclusion #8139 dependency.
• Adds meets_tanf_work_requirements, an SPM-unit bridge over existing DC and Montana TANF work-compliance variables.
• Wires the pass-through into medicaid_work_requirement_eligible through period.first_month.

Requirements Coverage

Requirement	Coverage
Medicaid CE pass-through primitive	medicaid_community_engagement_pass_through_eligible
SNAP-only pass-through	SNAP receipt plus person-level SNAP work compliance tests
TANF-only pass-through	is_tanf_enrolled plus meets_tanf_work_requirements tests
No-pass-through cases	SNAP/TANF negative tests and Medicaid work requirement false paths
Avoid #8139 dependency	Does not consume meets_snap_work_requirements

Not Modeled

• Application or renewal lookback periods.
• CMS reliable-data verification workflows.
• New TANF work-requirement formulas for states without existing state TANF work variables.
• SNAP household-wide work-requirement bug SNAP work requirements applied as household-wide disqualification instead of per-person exclusion #8139.

Validation

• uv run policyengine-core test policyengine_us/tests/policy/baseline/gov/hhs/medicaid/eligibility/medicaid_community_engagement_pass_through_eligible.yaml policyengine_us/tests/policy/baseline/gov/hhs/medicaid/eligibility/medicaid_work_requirement_eligible.yaml policyengine_us/tests/policy/baseline/gov/hhs/tanf/cash/eligibility/meets_tanf_work_requirements.yaml -c policyengine_us -v
  • 19 passed.
• make format
  • Passed.
• uv run policyengine-core test policyengine_us/tests/policy/baseline/gov/hhs/medicaid policyengine_us/tests/policy/baseline/gov/hhs/tanf/cash/eligibility/meets_tanf_work_requirements.yaml -c policyengine_us
  • 228 passed after rebasing onto current upstream/main.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.00%. Comparing base (8f458cd) to head (f51c86b).
⚠️ Report is 28 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##              main     #8368   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files            4         3    -1     
  Lines           52        66   +14     
=========================================
+ Hits            52        66   +14     

Flag	Coverage Δ
unittests	100.00% <100.00%> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.