chore: Upgrade action runtime from Node.js 20 to Node.js 24

[yysu]

Summary

• upgrade the GitHub Action runtime from node20 to node24
• update local Node version config from 20.8.1 to 24.14.0
• replace @tsconfig/node20 with @tsconfig/node24
• upgrade TypeScript from 5.6.3 to 5.9.3 so the Node 24 tsconfig can compile correctly
• regenerate bundled outputs in lib/index.js and lib/cleanup/index.js

Verification

• ran npm install
• ran npm exec --package=node@24.14.0 --call "npm run build && npm run lint"

Notes

• this repository does not currently define an npm test script, so there was no separate automated test suite to run

[yysu]

Related Issues:

• NodeJs 20 actions are deprecated #448
• Update Node to v24 #446