feat: 添加分享结果卡片功能，形成用户增长闭环

- 新增 ShareCardModal 组件，支持餐厅匹配和盲盒契约两种分享卡片
- 卡片包含品牌标识、匹配结果、餐厅/想法详情、二维码
- 使用 html-to-image 生成高清 PNG，支持保存图片和 Web Share API 分享
- 餐厅图片通过 canvas 转 data URL 处理跨域
- 集成到 MatchResult（极速救场）和 BlindBox reveal（周末契约）

src/components/MatchResult.tsx

@@ -23,6 +23,7 @@ import {
 import { Restaurant, MatchType, RunnerUp, SceneType } from "@/types";
 import { fireCelebration, playChime } from "@/lib/celebrate";
 import { isRegistered } from "@/lib/userId";
+import ShareCardModal from "@/components/ShareCardModal";
 
 interface MatchResultProps {
   restaurant: Restaurant;
@@ -183,6 +184,7 @@ export default function MatchResult({
 }: MatchResultProps) {
   const router = useRouter();
   const [showRunnerUps, setShowRunnerUps] = useState(false);
+  const [showShareCard, setShowShareCard] = useState(false);
   const [toast, setToast] = useState("");
   const celebratedRef = useRef(false);
   const historySavedRef = useRef(false);
@@ -223,46 +225,9 @@ export default function MatchResult({
     }).catch(() => {});
   }, [userId, roomId, restaurant, matchType, userCount]);
 
-  const handleShare = useCallback(async () => {
-    const verb = scene === "drink" ? "喝" : "吃";
-    const lines = [
-      isUnanimous
-        ? `🎉 默契度 100%！${userCount} 人全员一致选了同一家！`
-        : `🎉 我们用 NoWhatever 选好了去哪${verb}！`,
-      ``,
-      `📍 ${restaurant.name}`,
-      restaurant.rating ? `⭐ ${restaurant.rating}` : "",
-      restaurant.price && restaurant.price !== "未知" ? `💰 人均${restaurant.price}` : "",
-      restaurant.address ? `📮 ${restaurant.address}` : "",
-      ``,
-      isUnanimous ? `✨ 这就是心有灵犀吧～` : "",
-    ].filter(Boolean);
-
-    const text = lines.join("\n");
-    const navUrl = buildNavUrl(restaurant);
-
-    const shareData = {
-      title: `我们选了${restaurant.name}！`,
-      text,
-      url: navUrl,
-    };
-
-    try {
-      if (navigator.share && navigator.canShare?.(shareData)) {
-        await navigator.share(shareData);
-        return;
-      }
-    } catch (e) {
-      if (e instanceof Error && e.name === "AbortError") return;
-    }
-
-    try {
-      await navigator.clipboard.writeText(`${text}\n\n${navUrl}`);
-      showToast("已复制，快去发给朋友吧！");
-    } catch {
-      showToast("复制失败，请手动复制");
-    }
-  }, [restaurant, showToast, isUnanimous, userCount, scene]);
+  const handleOpenShareCard = useCallback(() => {
+    setShowShareCard(true);
+  }, []);
 
   if (matchType === "no_match") {
     return <NoMatchResult onReset={onReset} resetting={resetting} />;
@@ -451,12 +416,12 @@ export default function MatchResult({
           )}
 
           <motion.button
-            onClick={handleShare}
+            onClick={handleOpenShareCard}
             className="flex items-center justify-center gap-2 rounded-full bg-surface px-8 py-3 text-sm font-bold text-gray-300 ring-1 ring-border transition-colors hover:bg-elevated"
             whileTap={{ scale: 0.95 }}
           >
             <Share2 size={15} />
-            分享结果到群里
+            生成分享卡片
           </motion.button>
         </motion.div>
 
@@ -557,6 +522,20 @@ export default function MatchResult({
         </motion.div>
       </div>
 
+      <ShareCardModal
+        open={showShareCard}
+        onClose={() => setShowShareCard(false)}
+        data={{
+          type: "restaurant",
+          restaurant,
+          matchType,
+          matchLikes,
+          userCount,
+          scene,
+        }}
+        onToast={showToast}
+      />
+
       <AnimatePresence>
         {toast && (
           <motion.div