MA TAFDC: work-expense deduction credited to every member; eligibility test omits the 50% disregard

**Observed** (API, 2026 policy year): a married couple with three children (ages 1, 4, 9), one earner, no other income, in Massachusetts gets `tanf` = $9,880/yr at $26,000 of employment income and $0 at $27,000. The grant ends abruptly at $26,280.

**Cause**
- `ma_tafdc_work_related_expense_deduction` (`adds` the $200/month `work_related_expenses.amount` per Person) is credited to every SPM-unit member, including a 1-year-old. Probe: $2,400/yr on the infant. Countable income becomes earnings − $12,000 for a five-person unit.
- `ma_tafdc_financial_eligible` compares that figure to the payment standard without the 50% earned-income disregard (106 CMR 704.281(B)) that the grant calculation itself applies, so the case closes long before the grant reaches zero.

**Expected** (106 CMR 704.260, 704.270, 704.281(B), 704.500(A)): $200/month deducted per *earner*, then 50% of the remainder counted; the grant tapers at 50¢ per dollar and reaches $0 near $30,000–$30,960 for a five-person unit in private housing. There is no 185%-of-need gross screen. DTA's own worked example (FY2026 Standard Budgets report, family of three, private housing) gives $7,512/yr of TAFDC at $15,600 of earnings; the current formula gives less.

**Repro**: `POST /us/calculate` with people `you` (age 30, `employment_income` 26000 vs 27000), `spouse` (30), children 1/4/9; one `spm_unit` with `tanf: null`; `state_name: MA`.

**Sources**: 106 CMR 704 https://www.mass.gov/doc/106-cmr-704-transitional-cash-assistance-program-financial-eligibility/download · DTA Table of Need and Payment Standards https://www.mass.gov/doc/table-of-need-payment-standards/download · DTA FY2026 Standard Budgets report (Table 5).

Found while validating HotGap (a benefits-cliff calculator built on the API) against state sources.

Start with the ma_tafdc_work_related_expense_deduction and ma_tafdc_financial_eligible rules, then reproduce the POST /us/calculate example for the five-person Massachusetts case. Compare the results with 106 CMR 704.260, 704.270, 704.281(B), and 704.500(A); done means the deduction applies per earner, the 50% disregard is reflected, and the grant tapers toward zero rather than ending abruptly.

Written by the indexing model from the issue text.