v0.2.1 - npm run release: tag, push and GitHub Release in one command

[0.2.1] - 2026-10-15

Releases are a script now, not a habit: npm run release verifies the version
against the CHANGELOG, runs the tests, tags, pushes, and publishes the GitHub
Release.

Added

• npm run release (scripts/release.mjs): reads the version from
  package.json and refuses to run unless CHANGELOG.md carries a matching,
  non-empty ## [x.y.z] section and a [x.y.z]: link reference; requires a
  clean working tree on the release branch with the version bump already
  committed; runs node --test; pushes the release branch; creates the
  annotated tag v<x.y.z>; pushes it; and creates the GitHub Release through
  the REST API, using the tag annotation as the release title and the CHANGELOG
  section as its body.
  Credentials come from GITHUB_TOKEN / GH_TOKEN or git credential fill
  and are never printed. Flags: --title, --dry-run, --skip-tests,
  --branch, --remote.
• test/release.test.js: covers the argument parser, remote URL parsing,
  CHANGELOG section and link-reference extraction, and token resolution.

Changed

• package.json gains the release script. No published file changed.