Replace Google Maps with Esri (ArcGIS) basemaps

Swaps the map provider behind the existing provider-neutral JobMapProps
interface: EsriJobMap.tsx (ArcGIS Maps SDK) replaces GoogleJobMap.tsx,
loaded via esri-loader's CDN script rather than bundled through webpack —
next dev's inline source-mapping of a library this size was OOM-killing
the whole host on first compile. Also fixes a bug in the fit-bounds camera
call: view.goTo() needs real Graphic/Geometry instances, not plain point
literals, so the map was never zooming to the plotted points.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

docker-compose.yml

@@ -66,7 +66,7 @@ services:
       - /usr/src/app/node_modules
     environment:
       BACKEND_HOST: http://backend:3001
-      NEXT_PUBLIC_GOOGLE_MAPS_API_KEY: ${NEXT_PUBLIC_GOOGLE_MAPS_API_KEY:-}
+      NEXT_PUBLIC_ARCGIS_API_KEY: ${NEXT_PUBLIC_ARCGIS_API_KEY:-}
       NODE_ENV: development
     command: npm run dev