Fix the levels viewer: markers were drawn on whichever plan was showing

frontend/src/components/ShopFloorMap.vue

@@ -437,8 +437,18 @@ function renderMarkers() {
   overlayLayers.forEach(layer => layer.remove())
   overlayLayers = []
 
+  // Markers belong to ONE level (ADR-017). This is the drawing being shown, and
+  // anything positioned against a different one is not drawn on it.
+  const drawnLevel = drawnLevelId() ?? null
+
   props.machines.forEach(item => {
     if (item.mapx == null || item.mapy == null) return
+    // A marker from another level, placed on THIS blueprint, looks entirely
+    // correct and points at the wrong part of the building - so it is omitted
+    // rather than approximated. A position with no level at all is omitted for
+    // the same reason: the map editor lists both, badged, so they can be fixed
+    // rather than silently misplaced here.
+    if ((item.levelid ?? null) !== drawnLevel) return
 
     // Transform coordinates (database Y is top-down, Leaflet is bottom-up)
     const leafletY = MAP_HEIGHT - item.mapy
@@ -599,6 +609,31 @@ watch(() => props.theme, (newTheme) => {
   }
 })
 
+// Switching level changes the drawing, the coordinate space AND which markers
+// belong on it. All three move together: the size is what marker coordinates
+// mean, so swapping the image without the bounds would place every marker
+// against the wrong scale, and keeping the markers would show the previous
+// floor's assets on this floor's plan.
+watch(() => drawnLevelId(), (levelid) => {
+  if (!map || !imageOverlay) return
+
+  MAP_WIDTH = dimensionsFor(levelid).width
+  MAP_HEIGHT = dimensionsFor(levelid).height
+  const bounds = [[0, 0], [MAP_HEIGHT, MAP_WIDTH]]
+
+  const url = blueprintUrlFor(props.theme, levelid)
+  // A level with no blueprint is left blank rather than showing the previous
+  // one, which would be a floor plan labelled as somewhere it is not.
+  imageOverlay.setUrl(url || '')
+  imageOverlay.setBounds(bounds)
+
+  map.setMaxBounds(bounds)
+  map.setView([MAP_HEIGHT / 2, MAP_WIDTH / 2], map.getZoom())
+
+  renderMarkers()
+  loadOverlays()
+})
+
 onMounted(async () => {
   // Load this facility's blueprint + dimensions before building the map so
   // bounds and coordinate math use the right size. Falls back to defaults.