Use HTTP caching 💾

[opatry]

There might be HTTP requests that could be useless, especially for the auto refresh mechanism.

Evaluate if HTTP caching could be helpful.

See https://medium.com/@coreflodev/understand-offline-first-and-offline-last-in-android-71191e92b426

"Cache-Control", "only-if-cached, max-stale=cache-name"
// vs
"Cache-Control", "public, only-if-cached, max-stale=" + 60 * 60 * 24)

https://ktor.io/docs/client-caching.html