Review offline support

[bruno-garcia]

A customer who has a MAUI app that goes offline for extended amount of time has reported that events are getting lost.
No client reports indicate data being dropped.

I expected at least:

sentry-dotnet/src/Sentry/Internal/Http/CachingTransport.cs

Line 366 in cb67d21

_options.ClientReportRecorder.RecordDiscardedEvents(DiscardReason.CacheOverflow, envelope);

Reading the code it seems like we don't delete files if the failure reason is network connectivity:

sentry-dotnet/src/Sentry/Internal/Http/CachingTransport.cs

Lines 349 to 357 in cb67d21

	catch (Exception ex) when (IsNetworkError(ex))
	{
	if (_options.NetworkStatusListener is PollingNetworkStatusListener pollingListener)
	{
	pollingListener.Online = false;
	}
	_options.LogError(ex, "Failed to send cached envelope: {0}, retrying after a delay.", file);
	// Let the worker catch, log, wait a bit and retry.
	throw;

But I believe we should run some tests:

1. Put the simulator offline. Generate some events. Let the buffer fill (30 by default), do we get the client reports?
2. If the failure is a timeout, do we delete the issue (aka: review the heuristics for "Network Error")