Set Java/Android SDK options

[mattjohnsonpint]

This sets most of the Java/Android SDK options when using the net6.0-android target from the .NET SDK.

• Many options are shared between both SDKs, and are simply copied across.
• A few Java SDK options are hard-coded because they don't make sense any other way in this context.
• Several options available on the Java SentryOptions and SentryAndroidOptions are not available on ours at all, so I have exposed them on SentryOptions.Android and mirrored the defaults.
• Some to/from mapping functions are added where needed. Some map directly, others go through JSON serialization.
• I also refactored quite a bit, and fixed several TODOs (and added a few more)

This is also relevant for MAUI.

Note, #1692 and #1693 need to be in place before this works.
Also, we currently have no way to write unit tests for this code, but it's all been run manually several times on my box.

[bruno-garcia]

Looking great

[mattjohnsonpint]

I had to revert the last commit. I was attempting to map Java enums to C# enums using the recommended approach documented here. The library compiled fine, but generated the wrong method signature in the Android Callable Wrapper, so failed when building one of the sample apps. I hunted for a workaround but found none.

I need to raise this as an upstream issue to Microsoft, but in the meantime we can just keep things as they were.

[mattjohnsonpint]

FYI - the enum issue is reported here: dotnet/java-interop#991