Update transitive audit dependencies

[hauptmedia]

Summary

• update the locked form-data resolution from 4.0.5 to 4.0.6
• update the locked joi resolution from 17.13.3 to 17.13.4
• leave broader Docusaurus/webpack/sockjs audit findings untouched because they require upstream range changes

Verification

• node -e "const lock=require('./package-lock.json'); console.log('form-data', lock.packages['node_modules/form-data'].version); console.log('joi', lock.packages['node_modules/joi'].version);" prints form-data 4.0.6 and joi 17.13.4
• NODE_NO_WARNINGS=1 npm audit --json | node -e "..." reports total: 29, high: 1, moderate: 28, hasFormData: false, hasJoi: false
• git diff --check
• npm run build succeeds; it reports the known pre-existing main link/anchor warnings covered by separate docs quality work

Note: npm run typecheck still fails on raw main because TypeScript 6 deprecates baseUrl unless ignoreDeprecations is set. That existing config fix is already covered by separate docs quality/starter-cleanup PRs, so this PR keeps the dependency change narrow.