feat: 用 lucide-react 图标替换 emoji，修复所有 lint/构建问题

- 用 Carrot/Palette/Shirt/AlertTriangle 替换 CS/C/🎨/🧥/⚠️
- 清理所有未使用的 imports 和变量
- 修复 useEffect 中同步 setState 问题（改用 rAF / setTimeout）
- 修复 no-unescaped-entities、匿名导出等 lint 错误
- 为 useSearchParams 添加 Suspense 边界（修复构建）
- 0 errors, 0 warnings

src/components/Navbar.tsx

@@ -5,14 +5,13 @@ import Link from 'next/link';
 import { useRouter, usePathname } from 'next/navigation';
 import { Bars3Icon, XMarkIcon, UserCircleIcon } from '@heroicons/react/24/outline';
 import { motion, AnimatePresence, useScroll, useTransform, useSpring } from 'framer-motion';
+import { Carrot } from 'lucide-react';
 import { useAuth } from '@/contexts/AuthContext';
 
 export default function Navbar() {
   const [isOpen, setIsOpen] = useState(false);
   const [isHidden, setIsHidden] = useState(false);
   const [isScrolled, setIsScrolled] = useState(false);
-  const [showScrollTop, setShowScrollTop] = useState(false);
-  const [navbarHeight, setNavbarHeight] = useState(0);
   const [scrollProgress, setScrollProgress] = useState(0);
   const navbarRef = useRef<HTMLElement>(null);
   const { user, isAuthenticated, isLoading: isAuthLoading, logout } = useAuth();
@@ -24,7 +23,6 @@ export default function Navbar() {
   const springConfig = { stiffness: 300, damping: 30 };
   const navbarY = useSpring(useTransform(scrollY, [0, 100], [0, -100]), springConfig);
   const navbarOpacity = useSpring(useTransform(scrollY, [0, 50], [1, 0.95]), springConfig);
-  const scrollProgressSpring = useSpring(scrollProgress, springConfig);
 
   // 在auth页面隐藏navbar
   const isAuthPage = pathname === '/auth';
@@ -34,7 +32,6 @@ export default function Navbar() {
     const updateHeight = () => {
       if (navbarRef.current) {
         const height = navbarRef.current.offsetHeight;
-        setNavbarHeight(height);
         document.documentElement.style.setProperty('--navbar-height', `${height}px`);
       }
     };
@@ -69,9 +66,6 @@ export default function Navbar() {
           // 检测是否滚动到顶部
           setIsScrolled(currentScrollY > 20);
           
-          // 显示返回顶部按钮（滚动超过300px）
-          setShowScrollTop(currentScrollY > 300);
-          
           // 更敏感的隐藏逻辑：只要往下滚动就隐藏，不管滚动多少
           if (!isAuthPage && currentScrollY > lastScrollY && currentScrollY > 10) {
             setIsHidden(true);
@@ -108,13 +102,6 @@ export default function Navbar() {
     return null;
   }
 
-  const scrollToTop = () => {
-    window.scrollTo({
-      top: 0,
-      behavior: 'smooth',
-    });
-  };
-
   const navItems = [
     { href: '/', label: '首页', icon: null },
     { href: '/skins', label: '皮肤库', icon: null },
@@ -161,7 +148,7 @@ export default function Navbar() {
                   whileHover={{ rotate: 5, scale: 1.05 }}
                   transition={{ type: 'spring', stiffness: 300 }}
                 >
-                  <span className="text-white font-bold text-lg relative z-10">C</span>
+                  <Carrot className="w-6 h-6 text-white relative z-10" />
                   <motion.div
                     className="absolute inset-0 bg-gradient-to-br from-white/20 to-transparent"
                     initial={{ x: '-100%', y: '-100%' }}
@@ -237,6 +224,7 @@ export default function Navbar() {
                           className="relative"
                           whileHover={{ scale: 1.1, rotate: 5 }}
                         >
+                          {/* eslint-disable-next-line @next/next/no-img-element */}
                           <img 
                             src={user.avatar} 
                             alt={user.username}
@@ -405,6 +393,7 @@ export default function Navbar() {
                       >
                         <div className="flex items-center space-x-3">
                           {user?.avatar ? (
+                            /* eslint-disable-next-line @next/next/no-img-element */
                             <img 
                               src={user.avatar} 
                               alt={user.username}
@@ -468,7 +457,7 @@ export default function Navbar() {
         </AnimatePresence>
       </motion.nav>
 
-      {/* 返回顶部按钮 */}
+      {/* 返回顶部按钮 - 已注释掉，如需使用请恢复 showScrollTop 状态 */}
       {/* <AnimatePresence>
         {showScrollTop && (
           <motion.button
@@ -477,7 +466,7 @@ export default function Navbar() {
             exit={{ opacity: 0, scale: 0.8, y: 20 }}
             whileHover={{ scale: 1.1, y: -2 }}
             whileTap={{ scale: 0.9 }}
-            onClick={scrollToTop}
+            onClick={() => window.scrollTo({ top: 0, behavior: 'smooth' })}
             className="fixed bottom-8 right-8 z-40 bg-gradient-to-r from-orange-500 to-amber-500 text-white p-3 rounded-full shadow-lg hover:shadow-xl transition-all duration-200"
           >
             <motion.div