Expand Medicaid community engagement compliance pathways

[daphnehanse11]

Fixes #8666
Fixes #8571
Fixes #8572
Fixes #8574

Summary

• Use Medicaid MAGI household income for the community engagement income safe harbor.
• Add qualifying activity hours from work, community service, work programs, and less-than-half-time education.
• Add the seasonal-worker six-month average income pathway.
• Add the treatment-program participant exclusion.

Testing

• uv run python -m policyengine_core.scripts.policyengine_command test policyengine_us/tests/policy/baseline/gov/hhs/medicaid/eligibility/medicaid_work_requirement_eligible.yaml -c policyengine_us (37 passed)
• git diff --check

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.00%. Comparing base (47cb26b) to head (8e45ea6).
⚠️ Report is 17 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##              main     #8711   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files            3         8    +5     
  Lines           47       104   +57     
=========================================
+ Hits            47       104   +57     

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 Harness.
📢 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.