feat: add pause, unpause, show, hide events & hook it into broadphase

[dragoncoder047]

Please describe what issue(s) this PR fixes.

closes #844 mostly.

• Adds onPause, onUnpause, onHide, onUnhide
• renames onResize for good measure too
• hooks the broadphase to add and remove objects when they're paused or unpaused, rather than just always skipping them (the performance impact should be negligible since it's just strange to be spam unpausing and repausing objects every frame)

Summary

• Changeloged

[imaginarny]

Isn't the resize observer observing canvas? So if you have own canvas with dimensions set on page, it wouldn't trigger onTabResize even if window is resized until the canvas itself gets resized as well - which would be then misleading. Shouldn't it be kept as onResize then?

By default canvas is set to window viewport dimensions and is mostly used like that, but it's not the only way, if true.

[imaginarny]

Still should be marked as a breaking change, so add (!) in front

- - The `onHide` and `onShow` global handlers...
+ - **(!)** The `onHide` and `onShow` global handlers...

[imaginarny]

And would also remove the broadphase hooking since it's possible of ending up hurting the perf, or at least it's uncertain. I confirmed it with MF as well. Offscreen with sidescrollers might be a good example when paused/unpaused is triggered on and off a lot. Adding/removing for some broadphase algos can be in particular more expensive (inserting in all overlapping grid square or correct branch in quadtree).

With skipping we at least know what we are at now, no uncertainty after. So unless we do proper testing of it behaving in more situations across broadphase algos, I would rather remove for now. You can always revisit later, to not block the events feature itself. What do you think?