feat: Improve banner fetching logic and integrate Banner component

- Adjusted server logic in `/banners/active` to resolve timezone issues and ensure consistent date handling.
- Sorted active banners by creation date in descending order for better relevance.
- Integrated `Banner.astro` component into the homepage layout for displaying active banners.

src/pages/index.astro

@@ -1,5 +1,6 @@
 ---
 import Layout from "../components/Layout.astro";
+import Banner from "../components/Banner.astro";
 import Hero from "../components/Hero.astro";
 import Welcome from "../components/Welcome.astro";
 import EventsGrid from "../components/EventsGrid.astro";
@@ -75,6 +76,7 @@ const images = [
 ---
 
 <Layout>
+	<Banner />
 	<Hero id="hero" />
 	<Welcome id="welcome" />
 	<EventsGrid id="events" events={events} />