Server: Speed up SSR rendering

Replace i18next with intl-messageformat:
- Complex page: 400ms to 300ms

Switch from React/Next to SolidJS/Vite:
- Complex page: 300ms to 50ms (1.1s to 260ms on an atom CPU)
- Simple page: 30ms to 8ms

Alternatives:
- Windowing: not an option, as I wanted all the data to be available at any given time for easier search/navigation
- Client-Side Rendering only: not an option, as I wanted to keep server-side generated html
- Basic templating (with caching) and simple js for client-side interactivity: could be interesting to explore this direction