California CCHIP eligibility varies by county

California has a county-specific CHIP eligibility pathway that is not representable with the current state-level CHIP child income limit.

Policy detail:
- California County Children Health Initiative Program (CCHIP) is only available in Santa Clara, San Francisco, and San Mateo counties.
- It provides full-scope coverage to children ages 0-19 whose families have incomes between 266% and 322% FPL.
- DHCS describes this as above 266% to 322% FPL in its 2026 FPL program table.

Why this matters:
- `gov.hhs.chip.child.income_limit` is state-level, so it cannot distinguish the three CCHIP counties from the rest of California.
- Modeling this as statewide would overstate CHIP eligibility outside those counties; leaving California as no separate CHIP misses CCHIP eligibility in those counties.

Potential implementation direction:
- Add a county-aware California CCHIP eligibility condition, likely using `county_str`.
- Consider whether this belongs as a California-specific CHIP variable or as a more general geographic override pattern for CHIP income limits.

Sources:
- DHCS MEDIL I 26-12, Apr. 20, 2026: https://www.dhcs.ca.gov/services/medi-cal/eligibility/letters/Documents/I-26-12.pdf
- DHCS Program Descriptions by FPL, 2026: https://www.dhcs.ca.gov/services/medi-cal-resources/medi-cal-eligibility-division/all-county-welfare-directors-medi-cal-eligibility-division-information-letters/program-descriptions-by-fpl-enclosure-3/
- CMS eligibility levels note on California separate CHIP: https://www.medicaid.gov/medicaid/national-medicaid-chip-program-information/medicaid-childrens-health-insurance-program-basic-health-program-eligibility-levels