Remove spm_unit_capped_work_childcare_expenses as a hard calibration target

[MaxGhenis]

spm_unit_capped_work_childcare_expenses is currently a hard national calibration target, but it is a Census SPM survey construct rather than an authoritative administrative total.

Why the current target is weak:

• Census defines SPM_CAPWKCCXPNS as the SPM unit's capped work and child care expense, with separate survey variables for uncapped child care and uncapped work expenses.
• This is useful for preserving CPS/SPM alignment, but it is not comparable to admin-backed targets like IRS, SSA, CMS, or HHS program totals.
• There is no single authoritative administrative total for the combined SPM concept.

Potential replacements / diagnostics:

• HHS OCC CCDF caseload and expenditure data.
• TANF child care spending / CCDF transfers from ACF OFA.
• IRS Form 2441 dependent-care benefits and CDCC totals.

Proposed change:

• Remove spm_unit_capped_work_childcare_expenses from the hard calibration target set.
• If we want external anchors here, add component-level diagnostics or soft targets using CCDF, TANF child-care spending, and IRS Form 2441 totals instead of forcing the combined CPS SPM measure.

Primary sources:

• Census CPS ASEC variable list: https://api.census.gov/data/2025/cps/asec/mar/variables.html
• Census SPM technical documentation: https://www2.census.gov/programs-surveys/supplemental-poverty-measure/technical-documentation/spm_techdoc.pdf
• ACF OCC data portal: https://www.acf.hhs.gov/occ/data
• IRS Form 2441 overview: https://www.irs.gov/forms-pubs/about-form-2441