render_map_tool: smaller map ideas (isochrone slider, 3D tilt, night lighting, traffic refresh) #288

Smaller render_map_tool map ideas, grouped together. Each could be split out if picked up.

• Isochrone time slider:
  • Today an isochrone shows fixed contours.
  • A slider (say 5 to 30 minutes) would redraw the contour by refetching through the page's existing isochrone self-fetch.
  • It would need throttling so dragging doesn't fire a request per pixel.
• 3D tilt button:
  • The Standard style already has 3D buildings and landmarks, but the map opens flat and pitching it needs a right-drag that most users don't know about.
  • A button would toggle between 0° and about 60° of tilt.
• Night lighting when it's dark there:
  • Default lightPreset to dusk or night when it's dark at the map's location at render time.
  • Only when the model didn't set baseMapConfig.lightPreset.
  • It needs sunrise and sunset for the map center, which can be computed client-side.
• Refresh traffic while open:
  • Traffic tiles (feat(render_map_tool): live traffic and Satellite/Traffic buttons on the map #278) go stale on a map left open.
  • Refetch them every few minutes while the Traffic layer is on and the page is visible.