feat(profiling): generate chrome compatible timeline data

[rigor789]

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What is the current behavior?

Profiling requires installing an external tool (timeline-view) and piping the output of a run command into it to generate a timeline html view.

What is the new behavior?

A timeline json file is generated automatically when timeline profiling is enabled (profiling: "timeline" in the nativescript config). The file is saved when the run is canceled with ctrl+c. The output json can be loaded into chrome devtools -> Performance and loading the json.

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Commented out the SIGINT handling override - as it prevented listening for it for writing the timeline jsons - however this might cause side effects, so a different approach might be required.

For example and idle timeout, if no new traces come in within X seconds, it's automatically saved.

Another approach is listening for a keypress (for example s for "stop") and then stopping the timeline.

Other...?

Found a different approach by getting around the SIGINT prevention only when profiling.