Generating routes for user-land Vite in user's dir

[infomiho]

This PR is not for reviewing. It might serve for discussion later on.

What was done:

• Generates the routes in user-land in router.generated.tsx
• Uses the generated routes in the getWaspApp helper that returns the WaspApp component that needs to be mounted in the index.tsx
• Alongside the routes changes, we also import the app.client.rootComponent and the app.client.setupFn directly in index.tsx

Part of #3135 #3472