fix(video360): prevent teardown crash when closing 360 video preview

[zhirongwang]

Summary

• Separate 360 controls into video360Controls so teardown no longer calls removeListener() on DashViewer's React ControlsRoot
• Tear down 360 controls before super.destroy() to avoid double-destroy and early-unmount crashes
• Add regression test for destroy when only React controls are present
  Fixes PREVIEW-1008

Test plan

• NODE_ENV=test yarn jest src/lib/viewers/box3d/video360/__tests__/Video360Viewer-test.js
• Open a .360.mp4, close/navigate away before viewer fully loads — no console TypeError
• Open a .360.mp4, wait for interactive viewer, then close — clean teardown
• Back button from 360 preview returns to folder listing (no "Oops" page)

[CLAassistant]

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[aivkov123]

LGTM