Fix MA TAFDC income-test boundary and IL TANF minimum payment

[MaxGhenis]

Summary

TANF review covering three issues. Two produced verified code fixes (MA, IL); one (NY) was already fixed on main and is confirmed correct against the primary source, so it needs no change.

Massachusetts TAFDC financial eligibility — fixes #8790

Verified against 106 CMR 704.260. The regulation's income test is inclusive at the applicable Need Standard: total countable income "does not exceed" — i.e. "the assistance unit is eligible" when income "is equal to or is less than the appropriate Need Standard." PolicyEngine used a strict <, so a filing unit whose income exactly equals the standard was wrongly found ineligible.

• ma_tafdc_financial_eligible: changed income < payment_standard to income <= payment_standard; retargeted the reference to 704.260.
• On the second concern in the issue (payment standard vs. Need Standard): PolicyEngine's ma_tafdc_payment_standard is built from the TAFDC income-limit (Need Standard) tables, so it is the applicable Need Standard for this test. No separate variable is needed; documented inline.
• Tests: added inclusive-boundary cases (income exactly equal to the Need Standard → eligible; one dollar above → ineligible).

Illinois TANF minimum payment and income eligibility — fixes #8761

Verified against IDHS PM 10-01-02 (WAG 10-01-02), manual item 15820:

A family qualifies for TANF benefits, if nonexempt income is at least $1 less than the Payment Level for the unit's size. TANF payments of less than $1 are not made. When the monthly benefit amount would be less than $1, eligibility for cash does not exist. … Regular monthly TANF benefits and Initial Prorated Entitlement (IPE) payments are rounded down to the nearest whole dollar.

• New dated parameter gov.states.il.dhs.tanf.minimum_payment ($1).
• il_tanf_income_eligible: changed income <= payment_level to payment_level - income >= minimum_payment (income equal to or above the payment level is ineligible).
• il_tanf: floor the regular monthly benefit to whole dollars and pay nothing when the floored benefit is below the minimum.
• Tests: added rounding and minimum-payment boundary cases; updated existing integration expectations to the floored amounts (e.g. 469.50 → 469, 237.06 → 237, 109.81 → 109, 325.75 → 325, 51.75 → 51); converted three unit tests from annual to monthly periods so the per-month rounding is exercised honestly.

New York earned income disregard — #8835 (no change needed)

The 62/63/64% disregard (effective 2023-06-01 / 2024-06-01 / 2025-06-01), keeping 50% dated to 2022-10-01, already landed on main in #8912. Primary-source review confirms the values and the disregard order (percentage EID first, then the $150 work-expense disregard, which PolicyEngine already carries):

• 23-ADM-04: "Effective June 1, 2023, the EID will increase from 50% to 62%"; net income compared to the standard of need "after deducting the 62% EID and then the $150 work expense disregard."
• 24-ADM-04: "Effective June 1, 2024, the EID increased from 62% to 63%."
• 25-ADM-04: "Effective June 1, 2025, the EID increased from 63% to 64%."

The shelter-allowance sub-note in #8835 (PE's 277/283/400/... vs. an alternate 214/219/309/... schedule) is a county-schedule modeling question, not a value error, and is not resolved here.

Testing

All run with policyengine_core.scripts.policyengine_command test … -c policyengine_us:

• NY TANF: 64 passed
• MA TAFDC: 146 passed; full MA state tree: 369 passed
• IL TANF: 121 passed; full IL state tree: 745 passed (no downstream regressions in programs that consume il_tanf / ma_tafdc)

🤖 Generated with Claude Code

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.00%. Comparing base (f9e58e7) to head (e245559).
⚠️ Report is 127 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##              main     #8918   +/-   ##
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  Coverage   100.00%   100.00%           
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  Files            3         3           
  Lines           55        42   -13     
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- Hits            55        42   -13     

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

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