feat: 用户名密码登录注册系统

- 新增 /api/auth/register 和 /api/auth/login 接口，使用 bcryptjs 哈希密码
- User 模型改为 username + passwordHash，id 自动生成 cuid
- 新增 AuthModal 组件（登录/注册双标签页），替换旧的 ProfileSetupModal
- 重写 /profile 页面：支持修改用户名、密码、头像、绑定邮箱、退出登录
- /api/user PUT 支持密码修改（需验证当前密码）和用户名唯一性校验
- 游客模式保留，右上角显示"登录"按钮；登录后显示头像和用户名
- 全局 nickname -> username 重命名（types、SwipeDeck、RoomManageModal、buildRoomStatus）
- 新增 logout() 清除登录态并重新生成游客 UUID

src/app/api/user/favorite/route.ts

@@ -0,0 +1,72 @@
+import { NextRequest, NextResponse } from "next/server";
+import { prisma } from "@/lib/prisma";
+
+export async function GET(req: NextRequest) {
+  const userId = req.nextUrl.searchParams.get("userId");
+  if (!userId) {
+    return NextResponse.json([]);
+  }
+
+  const favorites = await prisma.favorite.findMany({
+    where: { userId },
+    orderBy: { createdAt: "desc" },
+    take: 50,
+  });
+
+  return NextResponse.json(
+    favorites.map((f) => ({
+      id: f.id,
+      restaurantData: JSON.parse(f.restaurantData),
+      createdAt: f.createdAt.toISOString(),
+    })),
+  );
+}
+
+export async function POST(req: NextRequest) {
+  const { userId, restaurant } = await req.json();
+
+  if (!userId || !restaurant) {
+    return NextResponse.json({ error: "缺少必要字段" }, { status: 400 });
+  }
+
+  const user = await prisma.user.findUnique({ where: { id: userId } });
+  if (!user) {
+    return NextResponse.json({ error: "请先设置个人资料" }, { status: 404 });
+  }
+
+  const existing = await prisma.favorite.findFirst({
+    where: {
+      userId,
+      restaurantData: { contains: `"id":"${restaurant.id}"` },
+    },
+  });
+
+  if (existing) {
+    return NextResponse.json({ id: existing.id, alreadyExists: true });
+  }
+
+  const fav = await prisma.favorite.create({
+    data: {
+      userId,
+      restaurantData: JSON.stringify(restaurant),
+    },
+  });
+
+  return NextResponse.json({ id: fav.id });
+}
+
+export async function DELETE(req: NextRequest) {
+  const { userId, favoriteId } = await req.json();
+
+  if (!userId || !favoriteId) {
+    return NextResponse.json({ error: "缺少必要字段" }, { status: 400 });
+  }
+
+  const fav = await prisma.favorite.findUnique({ where: { id: favoriteId } });
+  if (!fav || fav.userId !== userId) {
+    return NextResponse.json({ error: "收藏不存在" }, { status: 404 });
+  }
+
+  await prisma.favorite.delete({ where: { id: favoriteId } });
+  return NextResponse.json({ ok: true });
+}