fix(og): convert font buffers to ArrayBuffer for Satori compatibility

lib/og-helper.tsx

@@ -11,10 +11,21 @@ export async function getOgFonts() {
 
   try {
     console.log(`[OG] Loading fonts: bold=${boldFontPath}, regular=${regularFontPath}`);
-    const boldFont = readFileSync(boldFontPath);
-    const regularFont = readFileSync(regularFontPath);
+    const boldFontBuffer = readFileSync(boldFontPath);
+    const regularFontBuffer = readFileSync(regularFontPath);
+
+    // Satori (Vercel OG) strictly requires an ArrayBuffer, not a Node Buffer view.
+    const boldFont = boldFontBuffer.buffer.slice(
+      boldFontBuffer.byteOffset,
+      boldFontBuffer.byteOffset + boldFontBuffer.byteLength,
+    );
+    const regularFont = regularFontBuffer.buffer.slice(
+      regularFontBuffer.byteOffset,
+      regularFontBuffer.byteOffset + regularFontBuffer.byteLength,
+    );
+
     console.log(
-      `[OG] Fonts loaded successfully (${boldFont.length} and ${regularFont.length} bytes)`,
+      `[OG] Fonts loaded successfully (${boldFont.byteLength} and ${regularFont.byteLength} bytes)`,
     );
 
     return [