Improve performance

[felixmokross]

Ideas:

• add a server side cache to the frontend, e.g. Redis
• add a server side cache to the cms
• add a cdn which supports http caching
• move db closer to / into the app (or rather copies of the data, like the Remix website does)

Considerations:

• if Fly app stays configured to sleep when inactive (and as long as we don't have enough traffic), a CDN would have the advantage that there is never a delay when accessing the website
• consider Remix features like returning a promise from a loader to load secondary data in the background

[felixmokross]

Look into this https://community.fly.io/t/best-way-to-internally-send-a-request-to-all-running-vms/3939/3