Fix Map settings popover rendering under the Live map

The popover sat below Leaflet's map panes and controls (z-index up to
1000), so it was obscured by the map. Lift the control wrapper and popover
to z-index 1200 (with the click-catcher backdrop just under it) so the
menu renders above the map.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Web App/web/src/components/Dashboard.vue

@@ -437,7 +437,7 @@ onBeforeUnmount(() => {
                   <span class="h-1.5 w-1.5 rounded-full bg-current"></span>{{ flyingCount }} drones
                 </span>
                 <!-- Map settings -->
-                <div class="relative">
+                <div class="relative z-[1200]">
                   <button
                     type="button"
                     class="grid h-7 w-7 place-items-center rounded-md text-ink-muted transition hover:bg-surface-2 hover:text-ink"
@@ -449,8 +449,8 @@ onBeforeUnmount(() => {
                     <Icon name="settings" :size="16" />
                   </button>
                   <template v-if="mapMenu">
-                    <div class="fixed inset-0 z-10" @click="mapMenu = false"></div>
-                    <div class="panel absolute right-0 z-20 mt-1.5 w-64 p-3.5 shadow-lg">
+                    <div class="fixed inset-0 z-[1190]" @click="mapMenu = false"></div>
+                    <div class="panel absolute right-0 z-[1200] mt-1.5 w-64 p-3.5 shadow-lg">
                       <div class="eyebrow mb-2.5">Map settings</div>
                       <label class="flex items-center justify-between gap-3">
                         <span class="text-sm text-ink-secondary">Show live air traffic</span>