[analytics] introduce Analytics (consent) Data initialization

[pq]

Adds a new Analytics service built on a DTDProcess that checks analytics status and can be run before DAS startup.

For example,

...

UnifiedAnalyticsData analyticsData = Analytics.initialize(sdk);

// Pass in data or a flag to indicate if analytics should be enabled for this run.
startServer(sdk);
...

There are a few TODOs and a concurrency issue to address but this seems to be holding up under a bunch of local testing and is big enough to merit a look before I do more wiring up.

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[helin24]

I think this looks reasonable! Do we have a sense of how long this checking takes? I'm assuming it wouldn't make sense to start analysis server without analytics and then restart it when DTD is up?

[helin24]

Is !! necessary in all of these instances? Can we instead lateinit or something like that?

[pq]

I'm a little leery of lateinit since it's so global but I'm with you that this looks gross. I'll investigate on the next pass.

Thanks for the nudge!

[pq]

Getting timing analytics would be a great idea. I think in the common case it will be VERY fast but at the corners, dunno.

Will add a TODO.

Thanks!