publish: write edited notes to the committed release-notes file, not only the GitHub Release #784

This was generated by AI during triage.

Found while reviewing #761.

Agent Brief

Category: bug
Summary: When a notes region has been edited, the per-version release-notes file committed to main must contain the same text as the GitHub Release body.

Current behavior:
At standing-PR publish, the notes step regenerates release notes and writes the per-version files (notes.releaseNotes.file.dir), which are committed so that, in the code's words, "main matches the GitHub release body". Edited regions from the PR body are applied afterwards, and only to the notes passed to the GitHub-release step. With an edited region, the GitHub Release shows the edit while release-notes/<version>.md on main keeps the regenerated text. This applied to package-keyed edits before #761 and now applies to sync too.

Desired behavior:

• For every key with an edited region, the committed per-version notes file contains exactly the text published as that package's GitHub Release body.
• The draft-then-dispatch flow behaves the same way.
• With no edits, behaviour is unchanged.

Key interfaces:

• publishFromManifest: the notes-generation, notes-file commit and edited-notes merge order.
• publishFromDraft and the editedNotes it passes to runRelease.
• The per-version notes file writer.

Acceptance criteria:

• Through publishFromManifest with an edited region and releaseNotes.file.dir set, the committed file's content equals the release body passed to publish (sync and per-package cases).
• The same holds through publishFromDraft.
• Publish without edits commits the same files as before.

Out of scope:

• Deciding whether an untouched bot seed counts as an edit (standing PR: refresh unedited notes regions instead of freezing the first seed #782).