Preload csss & js, add skeleton graphs for loading

templates/partials/skeleton_graph.html

@@ -0,0 +1,17 @@
+<div class="w-full h-full bg-gray-100 rounded-lg animate-pulse relative overflow-hidden">
+    <!-- Subtle shimmer effect -->
+    <div
+        class="absolute inset-0 bg-gradient-to-r from-transparent via-white/20 to-transparent -translate-x-full animate-[shimmer_2s_infinite]">
+    </div>
+    <div class="flex items-center justify-center h-full">
+        <div class="text-xs text-gray-400 font-medium">Loading...</div>
+    </div>
+</div>
+
+<style>
+    @keyframes shimmer {
+        100% {
+            transform: translateX(100%);
+        }
+    }
+</style>