Fix Hawaii itemized income and sales tax deduction limits

[PavelMakarchuk]

Fixes #9327.

Apply Hawaii's federal AGI limits to itemized income or sales taxes: $100,000 single/separate, $150,000 head of household, and $200,000 joint/surviving spouse. Eligibility ends at equality; real estate taxes remain deductible.

The parameter covers 2021 onward, consistent with existing Hawaii parameters. Sources: HRS 235-2.4(k)(2), 2021 instructions, and 2025 instructions.

Validation on 51741ec:

• All 458 Hawaii baseline tests passed through the actual PolicyEngine test runner, including 25 new cases covering boundaries, years, federal versus Hawaii AGI, income/sales election, local sales tax, spouse property-tax aggregation, and downstream deductions/standard-deduction fallback.
• Fixed initial fixture failures by explicitly setting local sales tax; omitted inputs otherwise invoke the existing modeled local sales tax.
• Complete review-program workflow plus incremental review: no unresolved correctness findings; official PDFs and cited pages verified.
• make format and git diff --check passed. Broader GitHub CI remains pending.

Local validation used the existing environment with the compatible spm-calculator 1.0.0.post1 wheel unpacked to a temporary PYTHONPATH directory; the shared environment was not modified.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.00%. Comparing base (909176a) to head (51741ec).
⚠️ Report is 37 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##              main     #9597   +/-   ##
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  Coverage   100.00%   100.00%           
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  Files            4         1    -3     
  Lines           76        17   -59     
  Branches         2         0    -2     
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- Hits            76        17   -59     

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

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[PavelMakarchuk]

Program Review — incremental

Source Documents

• Reviewed head SHA: 51741ec
• Mode: incremental from bc890d7; ancestry verified.
• Scope: corrected sales-election fixtures and three new deduction integration cases. Production formula, parameters and citations are unchanged.
• Reused verified 2021 N-11 instructions, 2025 N-11 instructions, and HRS 235-2.4(k)(2).

Findings

• C1 — RESOLVED: All three failed fixtures now explicitly set local sales tax to zero. The real engine passes all Hawaii baseline tests, confirming the correction.
• A1 — RESOLVED: Added income/sales-tax election cases with nonzero local taxes, property-tax preservation, deduction aggregation, standard-deduction fallback and taxable-income assertions. Arithmetic independently checked and tests passed.
• No critical or substantive findings remain. Optional zero-tax/mixed-status cases and test naming conventions remain minor suggestions (S1/S2).

Validation

• Real PolicyEngine test runner: 458 passed, 1 warning across the complete Hawaii baseline suite (29.75 seconds).
• Used the existing environment plus temporary unpacked spm-calculator==1.0.0.post1, within the project dependency range; no shared environment modification.
• GitHub CI remains pending on run 36035207024. Local passing tests are not a claim that CI passed.
• Original legal/PDF review: 10 filing-status value checks, zero mismatches; both added page references verified. Ninety pages rendered in the full review; cached evidence reused for this test-only update. Two review agents; no additional page rendering.

Review Severity: APPROVE

Ready for Ziming’s review. CI must finish before considering merge; no merge performed.