Fitness — read-only goal measurement

Inspect the active goals document and run only the caller-selected measurement, validation, drift, history, export, or meta-goal command.

Renamed from goals (2026-07-29): the semantic skill is fitness; the ao goals CLI command family is a separate product surface and keeps its name. A thin goals compatibility alias resolves to this skill.

Measurement stays trustworthy only because it cannot mutate what it measures; the moment a fitness report edits a goal, the next report measures the editor, not the project.

Named failure mode — advice creep: a measurement report that ends with "you should…" has silently become work selection.

Anti-pattern: padding the report with recommendations to look helpful. Corrective: return the numbers, the evidence gaps, and checked/not-checked scope, and let the caller decide.