chore: adopt .dev/ project-notes convention (pilot) — seeded from the 2026-07-05 deep review - #72

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: actions/checkout@v4, actions/setup-node@v4. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/

'currentChinese' is assigned a value but never used

'newSections' is assigned a value but never used

'oldSections' is assigned a value but never used

'expectedChineseContent' is defined but never used

'processor' is assigned a value but never used

'result' is assigned a value but never used

'result' is assigned a value but never used

'newTarget' is assigned a value but never used

'body' is assigned a value but never used