ui(mapillary): drop the keyless empty state

The panel no longer shows a separate keyless call-to-action; the fieldset
gate and the layer-row tooltip already cover the missing-key case. The
planner flag is tri-state (null until status answers).

Co-Authored-By: Claude Fable 5.1 <[email protected]>

docs/CURRENT-STATE.md

@@ -2697,7 +2697,8 @@ its criteria cannot be silently ignored.
 
 Street Level (Mapillary) lives in the right context rail next to CCTV as an
 ordinary collapsible panel and starts collapsed. Without `MAPILLARY_CLIENT_TOKEN`
-the panel shows a gated empty state naming the variable; with it, coverage
+the header status reads KEY REQUIRED and the controls stay disabled (key setup
+is documented in the README's Street Level section); with it, coverage
 draws as ground-clamped sequence lines (z0–5 overview points from orbit,
 z11–14 sequences below 60 km) and the proxy strips the unused `image` point
 layer from z14 tiles in transit (12 MB → ~80 KB). The plain-English query box