Align CHIP calibration to FY2024

[daphnehanse11]

Fixes #8096.

Summary

• Adds FY2024 MACPAC Exhibit 33 spending rows to CHIP total, federal, state, Medicaid-expansion, separate-CHIP, and program-admin calibration parameters.
• Adds FY2024 MACPAC Exhibit 32 enrollment rows to total, Medicaid-expansion, and separate-CHIP enrollment calibration parameters.
• Updates per_capita_chip_gross documentation now that 2024 net spending, enrollment, and cost-sharing offsets are aligned to FY2024.
• Updates per-capita CHIP tests and adds representative FY2024 gross checks for MO, FL, TX, and NY.

Sources

• MACPAC Exhibit 33, CHIP Spending by State FY2024: https://www.macpac.gov/publication/chip-spending-by-state/
• MACPAC Exhibit 32, Child Enrollment in CHIP and Medicaid by State FY2024: https://www.macpac.gov/publication/child-enrollment-in-chip-and-medicaid-by-state/
• Existing CMS FY2024 CHIP cost-sharing offsets: https://www.medicaid.gov/medicaid/financial-management/state-expenditure-reporting-for-medicaid-chip/expenditure-reports-mbescbes

Tests

• uv run --extra dev ruff format policyengine_us/variables/gov/hhs/chip/per_capita_chip_gross.py
• uv run python -m policyengine_core.scripts.policyengine_command test policyengine_us/tests/policy/baseline/gov/hhs/chip/per_capita_chip.yaml policyengine_us/tests/policy/baseline/gov/hhs/chip/per_capita_chip_gross.yaml -c policyengine_us
• uv run pytest policyengine_us/tests/test_parameter_files.py -q
• uv run --extra dev ruff check .

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.00%. Comparing base (d55cd4f) to head (6311d5e).
⚠️ Report is 91 commits behind head on main.

Additional details and impacted files

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  Coverage   100.00%   100.00%           
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  Files            2         1    -1     
  Lines           35        21   -14     
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- Hits            35        21   -14     

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

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[daphnehanse11]

Initial review pass before edits:

• Checked the CHIP FY2024 calibration parameter additions, existing parameter metadata/reference surfaces, per_capita_chip_gross period handling, the zero-enrollment guard, and the new CHIP test periods/error margins.
• I do not see a functional blocker yet.
• I did spot a small test-style cleanup opportunity: keep the new per_capita_chip case appended after existing cases and normalize the newly added CHIP test names to the numbered Case N, ... pattern.

I am patching those low-risk cleanups in a fresh detached /tmp worktree and will run the narrow CHIP tests/lint before pushing.

[daphnehanse11]

Code-quality pass pushed in c3982ea. I tightened the CHIP calibration parameter metadata so the labels/descriptions match the total/enrollment series more specifically. Focused CHIP YAML tests pass locally: 9 passed. The failing Full Suite states-non-ny-shard-1 job is unrelated to this PR; it is a NJ/NM/OH state income-tax baseline cluster that reproduces outside the CHIP calibration files.

[MaxGhenis]

Pushed a fix in 6311d5e for the Maryland denominator outlier.

MACPAC Exhibit 32's FY2024 Maryland row reports only 0.601k CHIP-funded children, while Exhibit 33 reports $682.9M in CHIP spending. Using that row directly made Maryland per-capita CHIP $1.136M. Since the FY2024 enrollment row is not comparable with the spending scope, this keeps Maryland's 2024 M-CHIP/total denominator on the prior same-scope 139k count until we have a comparable FY2024 denominator, and adds MD regression cases for both net and gross per-capita CHIP.

Local checks:

• uv run python -m policyengine_core.scripts.policyengine_command test policyengine_us/tests/policy/baseline/gov/hhs/chip/per_capita_chip.yaml policyengine_us/tests/policy/baseline/gov/hhs/chip/per_capita_chip_gross.yaml -c policyengine_us -> 11 passed
• .venv/bin/python -m pytest policyengine_us/tests/test_parameter_files.py policyengine_us/tests/code_health/parameters.py -q -> 3 passed

[MaxGhenis]

Reviewed the Maryland FY2024 denominator fix and current CI. The CHIP calibration update is now scoped consistently and all checks pass.