product-tracking-instrument-new-feature

Update the tracking plan when a feature ships, changes, or is removed. Assesses whether new events are needed, extends existing events with properties where possible, and produces a versioned mini-delta with changelog entry. Updates .telemetry/tracking-plan.yaml, delta.md, and changelog.md. Use when the user ships a new feature, modifies existing functionality, wants to keep tracking coherent as the product evolves, 'feature shipped,' 'new feature tracking,' 'update tracking for [feature],' 'what tracking does this feature need,' or 'instrument new feature.'