feat: Refactor layout and add toast notifications

This commit introduces a major structural refactoring by creating a shared application layout and integrates a toast notification system.

Key changes:
- A new `layout.tsx` file now contains the common Header and Footer components, ensuring a consistent structure across all pages.
- The main `page.tsx` has been simplified to only contain its specific content, with layout elements removed.
- The `react-toastify` library has been added to provide user feedback through toast notifications.
- Custom CSS styles have been applied to the toast notifications for a branded look and feel, including different gradient backgrounds for success, error, warning, and info states.
- The `.gitignore` file was updated to explicitly track the `.env` file, likely for an example configuration.

app/_components/HeaderButtons.tsx

@@ -0,0 +1,21 @@
+"use client";
+import Link from "next/link";
+import { usePathname } from "next/navigation";
+
+export default function HeaderButtons() {
+  const pathname = usePathname();
+  return (
+    <div className="flex justify-between items-center gap-5 mt-4 md:mt-0">
+      <Link
+        href={pathname.includes("contact-us") ? "/" : "/contact-us"}
+        className="text-(--primary)">
+        {pathname.includes("contact-us") ? "Home" : "Contact us"}
+      </Link>
+      <Link
+        href={"/login"}
+        className="bg-(--primary) text-white px-12 py-3 rounded-full">
+        Login
+      </Link>
+    </div>
+  );
+}