feat: add multilingual UI (EN/HI/MR) with language toggle

refactor: code cleanup and App.jsx component split

feat: commit remaining feature work

fix(ui): force responsive styles with !important flags and rebuild frontend

style(ui): refine mobile navbar with full-screen toggle and improved spacing

feat(ui): implement responsive mobile-first design with hamburger menu

refactor: update project branding and remove BAIF references

feat(ui): restyle frontend to match baif.org.in visual identity

Initial commit: BAIF Offline Translation Portal with production Dockerfile and recent optimizations