Add Santa Clara County General Assistance Program

[hua7450]

Summary

Adds Santa Clara County General Assistance (GA), a county-funded cash assistance program for indigent adults without dependent children.

This PR implements:

• Santa Clara County residency detection via in_scc.
• GA eligibility for single adults and married couples.
• Income, property, immigration, SSI, CAPI, CalWORKs, and self-employment eligibility rules.
• Monthly fill-the-gap benefit calculation: maximum aid payment minus countable income.
• Need Standards amounts for single adults, married couples, shared housing reductions, Board and Care, and medical institutions.
• Earned and unearned income treatment, including payroll/tax deductions and SSI-spouse income exclusion.
• Baseline and integration tests for the SCC GA rules.

Closes #8357

Regulatory Authority

• Cal. W&I Code § 17000 — state mandate requiring counties to relieve their indigent residents
• Cal. W&I Code § 17000.5 — optional state framework for a county GA standard of aid (not used by SCC)
• Santa Clara County GA Handbook — Policy chapter (GA 100-289)
• Chapter 2 — Eligibility for Other Programs (CalWORKs referral)
• Chapter 9 — Potential Income and Resources
• GA 282 — Shared Housing
• GA 180/181 — Personal Property
• GA 141 — Citizenship & Noncitizen Status
• Types of Income (GA 200-209)
• Need Standards Chart (GA 280)
• GA-62 Program Information Sheet

Main Rules Modeled

• Applicants must be Santa Clara County residents, age 18+, and either citizens or qualifying noncitizens.
• Personal property must be at or below the SCC GA limit.
• SSI recipients, CAPI-eligible applicants, active self-employed applicants, and CalWORKs-eligible households are not GA eligible.
• Married couples living together are aided as one case; unmarried adults are treated separately.
• Countable income includes earned income after modeled deductions plus listed unearned income sources.
• The benefit is capped at the applicable maximum aid payment and reduced dollar-for-dollar by countable income.

Need Standards Note

The Need Standards chart includes both percentage shared-housing rules and rounded whole-dollar table values. This PR keeps the percentage formula because the handbook states the operative shared-housing rule as a 15%, 20%, or 25% reduction.

The chart also includes 3-10+ person budget-unit rows. Those rows are not modeled here because the reviewed SCC application rules budget unmarried adults separately and aid only married couples together. I did not find a modeled pathway to a 3+ person GA budget unit in the provided policy PDFs.

Not Modeled

• 15-day continuous-presence residency requirement.
• Real-property deemed income.
• Sponsor deeming.
• Personal-property exemptions; inputs are treated as already net of exempt property.
• Nonfinancial GA 204 deductions such as meals, union dues, and work expenses without existing PolicyEngine variables.
• Public Works, job-search compliance, sanctions, voluntary-termination bars, IAR, Director's Exception, emergency support payments, special needs payments, and lump-sum disqualification.
• Immigration categories without matching PolicyEngine enum values, such as VAWA battered noncitizens, trafficking victims, and FAS citizens.

Tests

• policyengine-core test policyengine_us/tests/policy/baseline/gov/local/ca/scc/ -c policyengine_us -v — 107 passed
• make format — Ruff format unchanged; Ruff check passed
• CI passes

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.00%. Comparing base (ee131a9) to head (ac1a4d2).
⚠️ Report is 43 commits behind head on main.

Additional details and impacted files

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  Coverage   100.00%   100.00%           
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  Files            9        13    +4     
  Lines          149       181   +32     
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+ Hits           149       181   +32     

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

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