style(frontend): prettier baseline format (no logic change)

frontend/test/group.test.ts

@@ -4,8 +4,19 @@ import type { Book } from "../src/api/types";
 
 let seq = 1;
 const mk = (path: string): Book => ({
-  id: seq++, library_id: 1, path, title: path, format: "cbz", size: 1, mtime: 1, pages: 0,
-  state: "ready", error: "", added_at: "", percent: 0, cover_url: "/api/books/0/cover",
+  id: seq++,
+  library_id: 1,
+  path,
+  title: path,
+  format: "cbz",
+  size: 1,
+  mtime: 1,
+  pages: 0,
+  state: "ready",
+  error: "",
+  added_at: "",
+  percent: 0,
+  cover_url: "/api/books/0/cover",
 });
 
 it("根目录组为空串且排最前;目录组按字典序;组内保持输入顺序", () => {