Street Level: a landed link, a replaced photo and a retired lookup keep their state

- A link's photo step compares with the navigation token its own restore
  flight owned, so a navigation after the flight landed (while the layers
  still load) keeps the camera.
- A request that switches the source keeps the open photo up until it is
  replaced (holdViewer), so EXPAND stays across sources.
- A lookup given up while it looked leaves the open photo and the panel as
  they were, also when it found nothing or failed.
- A failed replacement shows its error inside the expanded viewer.
- A replacing lookup stops a playing Mapillary sequence before the found
  photo opens.
- The action refuses coordinates outside the globe, keeps a name given with
  coordinates as its label, and fly: false keeps the camera only for
  coordinates (its test-only entity and query branches are gone).
- Numbered entities carry their label; a view's street-level point is a pair.
- Mapillary's nearest search always asks for 50 m and 100 images.
- Tests: the lifecycle reproductions, PLAY on replacement, out-of-range
  coordinates, half a point, and the named label; three layer tests share
  enabledLayer; the second payload digest is gone.
- Docs: the tool count, the panel freshness rule, armed: false, the photo
  replacement, the browser-gate comment and a shorter changelog fragment.

src/voice/deixis.js

@@ -143,6 +143,8 @@ function resolveFly(args, { pointer, referents }) {
         entity: {
           layerId: target.layerId,
           id: target.id,
+          // The answer names it, not its id ("near cam-9").
+          ...(target.label ? { label: target.label } : {}),
           ...(hasPosition(target) ? { lat: target.lat, lon: target.lon } : {}),
         },
       },