refactor(seo): Improve page metadata and HTML semantics

This commit updates the page metadata (title and description) from the default Next.js placeholders to be descriptive of the Opp lens application, improving SEO.

Additionally, it refactors the HTML structure for better semantics and accessibility:
- Replaced generic `div` and fragment tags with appropriate semantic elements like `main`, `article`, `li`, and `small`.
- Corrected the heading hierarchy for better document structure.
- Fixed image source paths by making them absolute to prevent broken images.

app/(home)/layout.tsx

@@ -16,8 +16,8 @@ const geistMono = Geist_Mono({
 });
 
 export const metadata: Metadata = {
-  title: "Create Next App",
-  description: "Generated by create next app",
+  title: "Opp lens - AI-Powered Tender Management",
+  description: "Democratizing Tender Access for SMEs with AI-Powered Tender Management.",
   icons: {
     icon: "/fav-icon.svg",
   },
@@ -130,7 +130,7 @@ export default async function RootLayout({
           pauseOnHover
         />
 
-        <main className="container px-4 py-4 m-auto flex-grow">{children}</main>
+        <div className="container px-4 py-4 m-auto flex-grow">{children}</div>
         <footer className="relative h-full bg-[url('/footer-bg.svg')] bg-cover bg-no-repeat mt-40">
           <div className="relative z-10 container px-4 py-4 m-auto flex flex-col justify-center items-center mt-24 ">
             <div className="flex justify-between flex-col md:flex-row gap-14 w-full md:w-1/2">