Add Open Graph and Twitter Card metadata for social sharing

- Add og-image.jpg (1200x630) for link previews
- Add metadataBase, openGraph, and twitter metadata to layout.tsx
- Improves SEO and social media link appearance

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

app/layout.tsx

@@ -18,7 +18,30 @@ export const metadata: Metadata = {
     "Exploring regenerative economic systems inspired by mycelial networks and nature's resource allocation algorithms",
   generator: "v0.app",
   icons: {
-    icon: "/mycofi-logo.jpg",
+    icon: "data:image/svg+xml,<svg xmlns=%22http://www.w3.org/2000/svg%22 viewBox=%220 0 100 100%22><text y=%22.9em%22 font-size=%2290%22>🍄</text></svg>",
+  },
+  metadataBase: new URL("https://mycofi.earth"),
+  openGraph: {
+    title: "MycoFi - Mycoeconomics & Permaculture Currencies",
+    description: "Exploring regenerative economic systems inspired by mycelial networks and nature's resource allocation algorithms",
+    url: "https://mycofi.earth",
+    siteName: "MycoFi",
+    images: [
+      {
+        url: "/og-image.jpg",
+        width: 1200,
+        height: 630,
+        alt: "MycoFi - Regenerative Economics",
+      },
+    ],
+    locale: "en_US",
+    type: "website",
+  },
+  twitter: {
+    card: "summary_large_image",
+    title: "MycoFi - Mycoeconomics & Permaculture Currencies",
+    description: "Exploring regenerative economic systems inspired by mycelial networks and nature's resource allocation algorithms",
+    images: ["/og-image.jpg"],
   },
 }