refactor: suspense 로 페이지 감싸기

src/app/session/end/page.tsx

@@ -2,7 +2,7 @@
 "use client";
 
 import { useRouter, useSearchParams } from "next/navigation";
-import { useMemo, useState } from "react";
+import { Suspense, useMemo, useState } from "react";
 
 type Mode = "freeflow" | "sprint" | "deepwork";
 
@@ -30,7 +30,19 @@ function hhmmss(total: number) {
   return `${hh}:${mm}:${ss}`;
 }
 
-export default function SessionEndPage() {
+export default function Page() {
+  return (
+    <Suspense
+      fallback={
+        <main className="min-h-screen w-full" style={{ backgroundColor: BG }} />
+      }
+    >
+      <SessionEndInner />
+    </Suspense>
+  );
+}
+
+function SessionEndInner() {
   const router = useRouter();
   const params = useSearchParams();