feat: Add banner management feature and improve event/gallery image handling

- Introduced a new "Banners" feature, enabling banner creation, management, and display across the admin panel and frontend.
- Enhanced image handling for events and gallery by converting images to optimized webp format.
- Added `banners` table in the database schema for storing announcements.
- Integrated new `/api/banners` route in backend for banner operations.
- Updated `index.astro` to include banner display component.
- Added supporting UI and APIs in the admin panel for banner management.

src/pages/index.astro

@@ -1,6 +1,7 @@
 ---
 import Layout from "../components/Layout.astro";
 import Hero from "../components/Hero.astro";
+import Banner from "../components/Banner.astro";
 import Welcome from "../components/Welcome.astro";
 import EventsGrid from "../components/EventsGrid.astro";
 import Drinks from "../components/Drinks.astro";
@@ -76,6 +77,7 @@ const images = [
 
 <Layout>
 	<Hero id="hero" />
+	<Banner />
 	<Welcome id="welcome" />
 	<EventsGrid id="events" events={events} />
 	<ImageCarousel id="gallery" images={images} />