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

[dragoncoder047]

Please describe what issue(s) this PR fixes.

closes #844 mostly.

• Adds onPause, onUnpause, onHide, onUnhide
• renames conflicting global event hooks (& onResize for good measure too)
• fixes the sweepandprune to not create and destroy an iterator on every frame (by letting the sweepandprune drive the iteration instead of, y'know, using the iterator to basically have 2 loops controlling the iteration unnecessarily)

Summary

• Changeloged

[pkg-pr-new]

Open in StackBlitz

npm i https://pkg.pr.new/kaplayjs/kaplay@846

commit: 2514955