feat: 商家卡片支持多图展示，点击左右切换带 crossfade 过渡

- Restaurant.image 改为 images: string[]，API 层从高德取最多 5 张图
- RestaurantCard 新增 ImageGallery：点击图片左右区域切换、顶部圆点指示器、
  左右箭头提示、首次查看时文字引导气泡（2.5s 自动消失）
- 图片切换使用 crossfade 动画（旧图渐隐 280ms），过渡平滑
- MatchResult / Profile 页面兼容新旧数据格式，无图时条件渲染

src/components/RestaurantCard.tsx

@@ -1,7 +1,7 @@
 "use client";
 
-import { useCallback, useState } from "react";
-import { Star, MapPin, Clock, ExternalLink, Flame, Bookmark } from "lucide-react";
+import { useCallback, useState, useEffect } from "react";
+import { Star, MapPin, Clock, ExternalLink, Flame, Bookmark, ChevronLeft, ChevronRight } from "lucide-react";
 import { Restaurant } from "@/types";
 import { getUserId, isRegistered } from "@/lib/userId";
 
@@ -14,9 +14,115 @@ function stopAll(e: React.SyntheticEvent) {
   e.stopPropagation();
 }
 
+function ImageGallery({ images, name }: { images: string[]; name: string }) {
+  const [idx, setIdx] = useState(0);
+  const [fadingOut, setFadingOut] = useState<number | null>(null);
+  const [showHint, setShowHint] = useState(true);
+  const count = images.length;
+  const hasMultiple = count > 1;
+
+  useEffect(() => {
+    if (!hasMultiple || !showHint) return;
+    const t = setTimeout(() => setShowHint(false), 2500);
+    return () => clearTimeout(t);
+  }, [hasMultiple, showHint]);
+
+  const goTo = useCallback(
+    (newIdx: number) => {
+      if (newIdx === idx) return;
+      setFadingOut(idx);
+      setIdx(newIdx);
+    },
+    [idx],
+  );
+
+  const handleTap = useCallback(
+    (e: React.MouseEvent) => {
+      if (!hasMultiple) return;
+      e.stopPropagation();
+      e.preventDefault();
+      setShowHint(false);
+
+      const rect = e.currentTarget.getBoundingClientRect();
+      const tapX = e.clientX - rect.left;
+      const isRight = tapX > rect.width / 2;
+
+      const newIdx = isRight
+        ? Math.min(idx + 1, count - 1)
+        : Math.max(idx - 1, 0);
+      goTo(newIdx);
+    },
+    [hasMultiple, count, idx, goTo],
+  );
+
+  return (
+    <div className="relative h-full w-full" onClick={handleTap} onPointerDown={stopAll}>
+      <img
+        src={images[idx]}
+        alt={name}
+        className="absolute inset-0 h-full w-full object-cover"
+        draggable={false}
+        referrerPolicy="no-referrer"
+      />
+
+      {fadingOut !== null && (
+        <img
+          key={fadingOut}
+          src={images[fadingOut]}
+          alt=""
+          className="absolute inset-0 h-full w-full object-cover"
+          style={{ animation: "img-fade-out 280ms ease-out forwards" }}
+          onAnimationEnd={() => setFadingOut(null)}
+          draggable={false}
+          referrerPolicy="no-referrer"
+        />
+      )}
+
+      {hasMultiple && (
+        <>
+          <div className="absolute left-0 right-0 top-2 flex justify-center gap-1">
+            {images.map((_, i) => (
+              <span
+                key={i}
+                className={`h-[3px] rounded-full transition-all duration-200 ${
+                  i === idx
+                    ? "w-4 bg-white"
+                    : "w-1.5 bg-white/40"
+                }`}
+              />
+            ))}
+          </div>
+
+          {idx > 0 && (
+            <div className="pointer-events-none absolute left-2 top-1/2 -translate-y-1/2 rounded-full bg-black/25 p-1 backdrop-blur-sm">
+              <ChevronLeft size={20} className="text-white/90" />
+            </div>
+          )}
+          {idx < count - 1 && (
+            <div className="pointer-events-none absolute right-2 top-1/2 -translate-y-1/2 rounded-full bg-black/25 p-1 backdrop-blur-sm">
+              <ChevronRight size={20} className="text-white/90" />
+            </div>
+          )}
+
+          {showHint && idx === 0 && (
+            <div className="pointer-events-none absolute inset-x-0 top-1/2 -translate-y-1/2 animate-pulse text-center">
+              <span className="rounded-full bg-black/40 px-3 py-1 text-[11px] font-medium text-white/90 backdrop-blur-sm">
+                点击图片左右切换 · 共 {count} 张
+              </span>
+            </div>
+          )}
+        </>
+      )}
+    </div>
+  );
+}
+
 export default function RestaurantCard({ restaurant, likeCount = 0 }: RestaurantCardProps) {
   const [favorited, setFavorited] = useState(false);
 
+  const images = restaurant.images?.filter(Boolean);
+  const hasImage = images && images.length > 0;
+
   const handleFavorite = useCallback(async (e: React.MouseEvent | React.TouchEvent) => {
     e.stopPropagation();
     e.preventDefault();
@@ -45,15 +151,9 @@ export default function RestaurantCard({ restaurant, likeCount = 0 }: Restaurant
 
   return (
     <div className="flex h-full w-full flex-col overflow-hidden rounded-2xl bg-white shadow-xl">
-      <div className="relative h-[58%] w-full shrink-0 overflow-hidden">
-        <img
-          src={restaurant.image}
-          alt={restaurant.name}
-          className="h-full w-full object-cover"
-          draggable={false}
-          referrerPolicy="no-referrer"
-        />
-        <div className="absolute inset-0 bg-linear-to-t from-black/40 via-transparent to-transparent" />
+      <div className="relative h-[58%] w-full shrink-0 overflow-hidden bg-zinc-100">
+        {hasImage && <ImageGallery images={images} name={restaurant.name} />}
+        <div className="pointer-events-none absolute inset-0 bg-linear-to-t from-black/40 via-transparent to-transparent" />
 
         <div className="absolute bottom-3 left-4 flex items-center gap-1.5">
           {restaurant.category && (