Add favicon from RealFaviconGenerator

Downloads and integrates favicon assets (SVG, PNG, ICO, Apple touch icon,
web app manifest icons) and wires them up via Next.js metadata API in the
root layout.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/app/layout.tsx

@@ -21,6 +21,18 @@ const jetbrainsMono = JetBrains_Mono({
 export const metadata: Metadata = {
   title: "Candle Annotator",
   description: "Annotate candlestick charts for ML training",
+  icons: {
+    icon: [
+      { url: "/favicon.ico", rel: "shortcut icon" },
+      { url: "/favicon-96x96.png", sizes: "96x96", type: "image/png" },
+      { url: "/favicon.svg", type: "image/svg+xml" },
+    ],
+    apple: [{ url: "/apple-touch-icon.png", sizes: "180x180" }],
+  },
+  manifest: "/site.webmanifest",
+  appleWebApp: {
+    title: "Candle Annotator",
+  },
 };
 
 export default function RootLayout({