add proper flash messages

app/views/layouts/_merged_messages.haml

@@ -0,0 +1,28 @@
+#flash
+  -if flash.alert
+    .m-20.rounded.border-l-4.border-red-500.bg-red-50.p-4{:role => "alert"}
+      %strong.block.font-medium.text-red-700 Oops
+      %p.mt-2.text-sm.text-red-700
+        =flash.alert
+
+  -if flash.notice
+    .rounded-xl.border.border-gray-100.p-4.shadow-xl{:role => "alert"}
+      .flex.items-start.gap-4
+        %span.text-green-600
+          %svg.h-6.w-6{:fill => "none", :stroke => "currentColor", "stroke-width" => "1.5", :viewbox => "0 0 24 24", :xmlns => "http://www.w3.org/2000/svg"}
+            %path{:d => "M9 12.75L11.25 15 15 9.75M21 12a9 9 0 11-18 0 9 9 0 0118 0z", "stroke-linecap" => "round", "stroke-linejoin" => "round"}
+        .flex-1
+          %strong.block.font-medium.text-gray-900 Ok
+          %p.mt-1.text-sm.text-gray-700
+            = flash.notice
+
+:javascript
+  function hideNotice() {
+    const notification = document.querySelector('#flash')
+    if (notification) {
+      setInterval(function() {
+        notification.classList.add('collapse');
+      }, 5000);
+    }
+  }
+  hideNotice();

app/views/layouts/merged_layout.haml

@@ -46,4 +46,5 @@
                   %svg.h-5.w-5{:fill => "none", :stroke => "currentColor", "stroke-width" => "2", :viewbox => "0 0 24 24", :xmlns => "http://www.w3.org/2000/svg"}
                     %path{:d => "M4 6h16M4 12h16M4 18h16", "stroke-linecap" => "round", "stroke-linejoin" => "round"}
 
+    = render "layouts/merged_messages"
     = yield