[non-fatal-anr-support] Find the right polling interval and sane defaults #6208

We need to find sane defaults, which are a compromise between the level of detail and cpu overhead.

Main configuration knobs

• polling interval (frequency of checking the main thread, currently every 66ms (ref)
• the minimum hang duration, after which we start profiling the main thread, currently 1000ms (ref)
• the sampling interval, currently 66ms (same as polling interval)
• the minimum hang duration in order to report the hang as a non-fatal ANR (TBD, to be configurable by the end user)
  

Plan

• Add a demo screen to our sample app (TBD, maybe it's better to use a real app, https://github.com/Automattic/pocket-casts-android)
• Re-init the SDK with minimal settings, one with anr profiling enabled, and one without
• Run automated tests to measure the overhead