fix: shared link controls answer while the link restores

[paultursuru]

On a shared link, the about panel, the locate control and Back did
nothing until the two reverse geocodes that resolve the link's country
came back: seconds on a slow geocoder, the whole timeout if it failed.
Their listeners were registered after await restoreFromUrl().

• Register initLocateMe, initAboutDrawer and initNavigation
  before the restore.
• Hide the intro bubble on a link from the start, like the demo
  button already was: it sat over the map controls during the restore.
• state.restoring keeps a popstate during the restore (Forward onto
  the about entry) from restoring the link a second time.
• shared-link-restore.spec.js holds the reverse geocodes: the about
  panel opens and Back closes it, the locate control answers, and
  Forward does not restore twice. All three fail on main.