Update Calibration

Set or update a page's calibration; recompute affected measurements.

Atomic: writes scale_ratio + calibration columns and recomputes every linear/area measurement on the page in a single transaction. Returns the updated page detail and the count of recomputed measurements.

accepted_suggestion marks the write as an accepted detector read, the only thing that tells it apart from hand calibration; it is rejected 422 page_calibration_reduced_print_needs_confirmation on a reduced print unless confirm_reduced_print overrides (RUD-482, ADR-0152).

Per docs/superpowers/specs/2026-05-07-calibration-design.md §4.1, §4.3.