fix(maps): GPX overlay should stack below topbar elements

Ensure the GPX meta overlay stays below the app topbar (z-50).

Fixes # 380.

Author: Cassolette

packages/web-app-maps/src/components/GpxMap.vue

@@ -1,8 +1,8 @@
 <template>
   <div class="ext:flex ext:flex-col ext:relative ext:size-full">
-    <div ref="mapElement" class="ext:size-full ext:z-1" />
+    <div ref="mapElement" class="ext:size-full" />
     <dl
-      class="ext:absolute ext:grid ext:grid-cols-[auto_minmax(0,1fr)] ext:gap-x-4 ext:z-990 ext:bg-role-surface-container/80 ext:backdrop-blur-sm ext:rounded ext:p-3 ext:right-2 ext:top-2 ext:text-sm ext:shadow-sm"
+      class="ext:absolute ext:grid ext:grid-cols-[auto_minmax(0,1fr)] ext:gap-x-4 ext:bg-role-surface-container/80 ext:backdrop-blur-sm ext:rounded ext:p-3 ext:right-2 ext:top-2 ext:text-sm ext:shadow-sm"
     >
       <dt v-text="$gettext('Name')" />
       <dd>{{ meta.name }}</dd>