[obselate]

Changes

• Collect all four Changelog lines from Reuse plain-text layouts and fix hidden and nested scroll geometry #178 through Drop DevTools pipe clients on canceled IO #181 in a separate commit. The v0.7.39-to-main log contains no other PRs.
• Synchronize release references to 0.7.40 and date the notes 2026-10-20. Leave Unreleased empty.
• Regenerate 15 API pages and refresh the 29-file plugin reference mirror.

Verification

• Branch includes current origin/main. Posting account is obselate.
• release_version.py --check passes and --notes prints all four 0.7.40 entries.
• Onboarding and accessibility package validation pass.
• Locally packed Goo, Goo.Accessibility, Goo.DevTools, Goo.DevTools.App and Goo.Templates 0.7.40.
• Fresh isolated packed-template consumer builds against locally packed Goo with zero warnings and errors.
• API generator build passes with zero warnings and errors. Whitespace check passes.
• Android packaging and consumer checks are CI-only.
• Builds ran sequentially with nice -n 19, ionice -c3, -m:1 and disabled MSBuild/shared compilation servers. No NativeAOT build was run.

Do not merge or tag automatically. The integrator tags after merge.