Revert "update vite to version 6"

[tjkuson]

Reverts #12

npm ci fails:

npm error code ERESOLVE
npm error ERESOLVE could not resolve
npm error
npm error While resolving: @vitejs/plugin-react@4.3.3
npm error Found: vite@6.0.3
npm error node_modules/vite
npm error   dev vite@"^6.0.0" from the root project
npm error
npm error Could not resolve dependency:
npm error peer vite@"^4.2.0 || ^5.0.0" from @vitejs/plugin-react@4.3.3
npm error node_modules/@vitejs/plugin-react
npm error   dev @vitejs/plugin-react@"^4.3.3" from the root project
npm error
npm error Conflicting peer dependency: vite@5.4.11
npm error node_modules/vite
npm error   peer vite@"^4.2.0 || ^5.0.0" from @vitejs/plugin-react@4.3.3
npm error   node_modules/@vitejs/plugin-react
npm error     dev @vitejs/plugin-react@"^4.3.3" from the root project
npm error
npm error Fix the upstream dependency conflict, or retry
npm error this command with --force or --legacy-peer-deps
npm error to accept an incorrect (and potentially broken) dependency resolution.