better visual coherence

frontend/lib/modules/landmark_map_marker.dart

@@ -0,0 +1,57 @@
+import 'package:anyway/constants.dart';
+import 'package:anyway/structs/landmark.dart';
+import 'package:flutter/material.dart';
+
+
+class ThemedMarker extends StatelessWidget {
+  final Landmark landmark;
+  final int position;
+
+  ThemedMarker({
+    super.key,
+    required this.landmark,
+    required this.position
+    });
+
+  @override
+  Widget build(BuildContext context) {
+    // This returns an outlined circle, with an icon corresponding to the landmark type
+    // As a small dot, the number of the landmark is displayed in the top right
+
+    Widget? positionIndicator;
+    if (landmark.type != typeStart && landmark.type != typeFinish) {
+      positionIndicator = Positioned(
+        top: 0,
+        right: 0,
+        child: Container(
+          padding: EdgeInsets.all(5),
+          decoration: BoxDecoration(
+            color: Colors.grey[100],
+            shape: BoxShape.circle,
+          ),
+          child: Text('$position', style: TextStyle(color: Colors.black, fontSize: 25)),
+        ),
+      );
+    }
+
+    return RepaintBoundary(
+      child: Stack(
+        alignment: Alignment.topRight,
+        children: [
+          Container(
+            decoration: BoxDecoration(
+              gradient: APP_GRADIENT,
+              shape: BoxShape.circle,
+              border: Border.all(color: Colors.black, width: 5),
+            ),
+            width: 70,
+            height: 70,
+            padding: const EdgeInsets.all(5),
+            child: Icon(landmark.type.icon.icon, size: 50),
+          ),
+          if (positionIndicator != null) positionIndicator,
+        ],
+      ),
+    );
+  }
+}