feat(api): add stats chart endpoint for admin access with time series data

feat(dayjs): integrate dayjs for date handling and formatting across the application
refactor(routes): update date handling in id-tags, transactions, users, and dashboard routes to use dayjs
style(globals): improve CSS variable definitions for better readability and consistency
deps: add dayjs as a dependency for date manipulation

apps/web/app/dashboard/settings/page.tsx

@@ -4,6 +4,7 @@ import { useCallback, useEffect, useRef, useState } from "react";
 import { Alert, Button, CloseButton, Input, Label, Spinner, TextField, toast } from "@heroui/react";
 import { Fingerprint, Lock, Pencil, Person, TrashBin, Xmark, Check } from "@gravity-ui/icons";
 import { authClient, useSession } from "@/lib/auth-client";
+import dayjs from "@/lib/dayjs";
 
 type Passkey = {
   id: string;
@@ -411,11 +412,7 @@ export default function SettingsPage() {
                     {/* Date row: always visible */}
                     <p className="text-xs text-muted">
                       添加于{" "}
-                      {new Date(pk.createdAt).toLocaleString("zh-CN", {
-                        year: "numeric",
-                        month: "short",
-                        day: "numeric",
-                      })}
+                      {dayjs(pk.createdAt).format("YYYY年M月D日")}
                     </p>
                   </div>
                 </div>