Summary

• Updates dependency and security posture, including Castlabs Electron, Vite, Tailwind, electron-builder, and pnpm overrides for vulnerable transitive packages.
• Splits oversized files so every TypeScript/TSX source file is under the 450-line project limit.
• Adds English/Korean i18n with system-language detection, language settings, persisted preference, Chromium locale switch, and Accept-Language propagation.
• Replaces the stale README stable-release-in-November wording with Stage-0 beta wording and adds translation contribution docs.

Validation

• pnpm exec turbo run check-types lint build --force
• pnpm audit --prod=false
• TS/TSX 450-line check via find apps/browser/src -type f \( -name '*.ts' -o -name '*.tsx' \) -print0 | xargs -0 wc -l | awk '$2 != "total" && $1 > 450 {print; bad=1} END {exit bad}'
• git diff --check

Notes

GitHub reported existing vulnerabilities on the default branch during push; this branch's local pnpm audit --prod=false reports no known vulnerabilities.