feat(admin): add initial admin dashboard structure

This commit introduces the foundational structure for the new admin dashboard.

- Utilizes @nuxt/ui to build the dashboard layout, including a collapsible sidebar and navigation.
- Adds initial pages for the dashboard, news, events, and hall of fame management.
- Implements a composable `useDashboardSidebarLinks` for managing sidebar navigation.
- Refactors the default layout by integrating the header and footer directly.
- Swaps the primary and secondary theme colors across the application.

app/assets/css/main.css

@@ -1,2 +1,9 @@
-@import "./app.css";
-@import "./markdown.css";
+@import "./markdown.css";
+
+@import "tailwindcss";
+@import "@nuxt/ui";
+
+@theme {
+  --color-primary: #fb9e3a;
+  --color-secondary: #fcef91;
+}