Upgrade to React 19 and integrate shadcn/ui component library#17

Draft

Copilot wants to merge 11 commits intomainfrom

copilot/update-react-shadcn-ui

Commits on Jan 15, 2026

Initial plan
Copilot
committed
Initial exploration: understand current codebase structure

Copilot
and
4msar
committed
Update React to v19 and set up shadcn/ui component library

Copilot
and
4msar
committed
Replace custom UI with shadcn components and sonner toasts

Copilot
and
4msar
committed
Fix linting issues and improve code quality

Copilot
and
4msar
committed
Remove unused notistack dependency and useSnackbar hook

Copilot
and
4msar
committed
Add error handling for clipboard API and use variant prop for destructive action

Copilot
and
4msar
committed
Replace native prompt with Dialog for opening notes

Copilot
and
4msar
committed
Replace native confirm in Home page with AlertDialog for consistency

Copilot
and
4msar
committed
Improve clipboard error message clarity in save flow

Copilot
and
4msar
committed
Update README with modern tech stack and improved documentation

Copilot
and
4msar
committed