Update Existing Branch

Use this skill when the milestone branch set already exists and contains drafted markdown, features.json, reviewer comments, or human edits. The branch set is the base branch plus its per-component branches as defined in release-notes/references/pr-layout.md.

This is the incremental rerun stage of the release-notes pipeline. It is the branch-maintenance equivalent of what editorial-scoring is for scoring: the canonical place to describe how follow-up runs should behave.

Purpose

Treat the existing branch set as the working baseline, not as a blank slate.

The goal is to: