preserve _tags in cam cache, make line purple and thicker

lib/services/camera_cache.dart

@@ -13,7 +13,23 @@ class CameraCache {
   /// Add or update a batch of camera nodes in the cache.
   void addOrUpdate(List<OsmCameraNode> nodes) {
     for (var node in nodes) {
-      _nodes[node.id] = node;
+      final existing = _nodes[node.id];
+      if (existing != null) {
+        // Preserve any tags starting with underscore when updating existing nodes
+        final mergedTags = Map<String, String>.from(node.tags);
+        for (final entry in existing.tags.entries) {
+          if (entry.key.startsWith('_')) {
+            mergedTags[entry.key] = entry.value;
+          }
+        }
+        _nodes[node.id] = OsmCameraNode(
+          id: node.id,
+          coord: node.coord,
+          tags: mergedTags,
+        );
+      } else {
+        _nodes[node.id] = node;
+      }
     }
   }
 

lib/widgets/map_view.dart

@@ -417,8 +417,8 @@ class MapViewState extends State<MapView> {
         if (originalCoord != null) {
           lines.add(Polyline(
             points: [originalCoord, camera.coord],
-            color: Colors.orange.withOpacity(0.7),
-            strokeWidth: 2.0,
+            color: kCameraRingColorPending,
+            strokeWidth: 3.0,
           ));
         }
       }