Add guest cart drawer, Continue handoff, and shared customer login.

Co-authored-by: Cursor <cursoragent@cursor.com>

app/api/auth/me/route.ts

@@ -0,0 +1,10 @@
+import { getBearerToken, jsonResponse, meshkeeFetch, unauthorizedResponse } from "@/lib/meshkee-server";
+
+export async function GET(request: Request) {
+  const token = getBearerToken(request);
+  if (!token) return unauthorizedResponse();
+
+  const res = await meshkeeFetch("/auth/me", { token });
+  if (!res.ok) return jsonResponse({ error: "Unauthorized" }, res.status);
+  return jsonResponse(res.data);
+}