Refresh CPS-only fields on PUF support clones

[MaxGhenis]

Summary

• add a PUF support-clone CPS-only / clone-feature refresh stage after PUF income/tax fields are grafted
• rematch copied CPS-side fields from CPS rows using compatible demographics plus PUF-imputed income predictors
• reconcile Social Security subcomponents back to the PUF-imputed Social Security total and emit refresh diagnostics

Why

PUF support clones start as CPS copies, then receive PUF income/tax variables. Without a second refresh, copied CPS-side fields like disability, transfer, work, SPM, and clone-feature labels can remain tied to the original CPS income rather than the PUF-imputed income. This mirrors the eCPS two-stage principle in an MP-native way: use the new PUF-income surface when refreshing clone-side fields.

Notes

• eCPS separates clone-feature rematching from CPS-only QRF imputation; this PR implements a single nearest-neighbor rematch stage for the MP support-clone path so fields remain jointly coherent with PUF-imputed income.
• This does not rerun the full artifact; it is covered by focused pipeline tests around disability rematching and Social Security subcomponent reconciliation.

Tests

• uv run ruff check src/microplex_us/pipelines/us.py tests/pipelines/test_us.py
• uv run ruff format --check src/microplex_us/pipelines/us.py tests/pipelines/test_us.py
• uv run --extra dev python -m pytest tests/pipelines/test_us.py -q -k 'puf_support_clone_refresh or appends_puf_support_clone'