refactor(footer, header, robots): enhance accessibility, improve formatting, and update sitemap directives

app/metadata.tsx

@@ -1,31 +0,0 @@
-// app/metadata.ts
-
-import {Metadata} from "next";
-
-export const metadata: Metadata = {
-    title: "Dennis Konkol | Portfolio",
-    description: "Portfolio of Dennis Konkol, a student and software engineer based in Osnabrück, Germany. Passionate about technology, coding, and solving real-world problems.",
-    keywords: ["Dennis Konkol", "Software Engineer", "Portfolio", "Student"],
-    authors: [{name: "Dennis Konkol", url: "https://dki.one"}],
-    openGraph: {
-        title: "Dennis Konkol | Portfolio",
-        description: "Explore my projects and get in touch!",
-        url: "https://dki.one",
-        siteName: "Dennis Konkol Portfolio",
-        images: [
-            {
-                url: "https://dki.one/api/og",
-                width: 1200,
-                height: 630,
-                alt: "Dennis Konkol Portfolio",
-            },
-        ],
-        type: "website",
-    },
-    twitter: {
-        card: "summary_large_image",
-        title: "Dennis Konkol | Portfolio",
-        description: "Student & Software Engineer based in Osnabrück, Germany.",
-        images: ["https://dki.one/api/og"],
-    },
-};