Document peculiarities of NativeAOT and native crash reporting

* We should document this. And if this becomes a problem maybe we hook into the .NET assembly loading and invalidate any time that happens (as it could reference new native libs)?
* Offline caching of .NET layer is independentant of offline caching of native (which requires it to work) so it's not opt-in. Which directory it uses by default (could it affect macOS that requires user permission to write files on some directories?)

_Originally posted by @bruno-garcia in https://github.com/getsentry/sentry-dotnet/pull/2887#discussion_r1408125114_