Provide controls for player in Qt Design Viewer

When project is running on Qt Design Viewer, the overlay should show these controls

• restart button - restart player (clear)
• progress indicator for loading (before scene opens) (clear)
• should look good in browser (research)
  • option to scaled to browser window (default)
  • option WebGL has option to show design by pixels with scrollbars
    • 100% view
• screenshotting of the browser window / webgl context
  • draw a rectangle on top of webgl canvas -> call OS native screenshot functions
• annotation and commenting of the screenshots and images (research)
• image is on local clipboard (get granted when used OS native screenshotting)
• UX: design viewer to show modal that tells screenshot has been saved to local clipboard and design viewer is paused, OK button -> continue (research)

• pause & resume for running animation (research, does QML engine support this?)
  • icon showing the status of the player (playing, paused)
• provide WASD / Mouse / Touch controls for the project so it can be panned and viewed (esp. 3D projects)
  • during the export: check if WASD controller is present
  • mouse screen panning (WASM controls piped from web FE)
  • documentation & tutorial what web viewer compatible app requires
• stretch goal: run also on mobile / ipad