[v1.2.0] - 2026-06-18

Added

• New releasegen validate subcommand. Parses every ## [Unreleased] section
  in the repository and reports every malformed heading it finds — both
  across files and within a single file — in a single batched report. Detects
  ### Changed / ### Removed without the BREAKING CHANGE marker as well
  as any heading not declared in custom_change_types, naming the offending
  heading in each error. Needs no GitHub token, performs no I/O beyond reads,
  and exits 0 on success / 2 on any validation failure — intended as a
  required PR-time check before the release workflow.
• New .releasegen.yaml (also .releasegen.yml) config file at the repo root.
  Supports custom_change_types, exclude_dirs, a validate: block (see
  below), and the advanced self_release_module / self_release_repo
  overrides. Precedence is flags > env > file > built-in defaults; unknown
  keys cause a configuration error so typos surface early. Both validate
  and the existing release path read it, so repo-shape options no longer
  have to be duplicated across workflows.
• New optional --require-changelog-entry mode for releasegen validate
  (also exposed as validate.require_changelog_entry: true in
  .releasegen.yaml and RELEASEGEN_REQUIRE_CHANGELOG_ENTRY=true in the
  environment). When enabled, validate fails any PR whose non-CHANGELOG.md
  files changed vs the base ref but whose [Unreleased] section gained no
  new lines. Modules are scoped by where CHANGELOG.md lives, with the
  root changelog catching every file not claimed by a submodule changelog.
  The base ref is configurable via --base-ref / RELEASEGEN_BASE_REF /
  validate.base_ref and defaults to origin/$GITHUB_BASE_REF on GitHub
  Actions pull-request runs, else origin/main. Subsumes the prior
  external ensure_changelog workflow, which has been removed from this
  repository in favor of the validate-driven check.

Fixed

• Classifier no longer treats ### heading references in prose as real
  markdown headings. The internal heading3Prefix regex is now anchored
  to the start of a line (multiline mode), and fenced code blocks are
  stripped from [Unreleased] bodies before classification. Before this
  fix, an ### Added entry whose body documented ### Changed / ### Removed
  in an inline code span — and happened to mention BREAKING CHANGE while
  describing the marker rule — would be misclassified as a major bump.
  ValidateSection benefits from the same protection.