feat: 盲盒房间支持删除（创建者）和退出（成员）

- DELETE /api/blindbox/room/[code] 根据身份区分行为
- 房间页底部两步确认按钮，防止误操作
- 更新 ROADMAP：该功能从 P3 提升至 P1，移除低价值项

src/app/blindbox/[code]/page.tsx

@@ -14,6 +14,8 @@ import {
   Share2,
   LogIn,
   Copy,
+  Trash2,
+  LogOut,
 } from "lucide-react";
 import confetti from "canvas-confetti";
 import { getCachedProfile, isRegistered } from "@/lib/userId";
@@ -60,6 +62,8 @@ export default function BlindboxRoomPage() {
   const [showInvite, setShowInvite] = useState(false);
   const [showShareCard, setShowShareCard] = useState(false);
   const [toast, setToast] = useState("");
+  const [confirmLeave, setConfirmLeave] = useState(false);
+  const [leaving, setLeaving] = useState(false);
 
   const boxControls = useAnimation();
   const inputRef = useRef<HTMLInputElement>(null);
@@ -250,6 +254,36 @@ export default function BlindboxRoomPage() {
     handleCopyCode();
   };
 
+  const isCreator = profile?.id === room?.creatorId;
+
+  const handleLeaveOrDelete = async () => {
+    if (!confirmLeave) {
+      setConfirmLeave(true);
+      setTimeout(() => setConfirmLeave(false), 3000);
+      return;
+    }
+    if (leaving || !profile || !room) return;
+    setLeaving(true);
+    try {
+      const res = await fetch(`/api/blindbox/room/${room.code}`, {
+        method: "DELETE",
+        headers: { "Content-Type": "application/json" },
+        body: JSON.stringify({ userId: profile.id }),
+      });
+      if (!res.ok) {
+        const data = await res.json();
+        throw new Error(data.error || "操作失败");
+      }
+      router.replace("/blindbox");
+    } catch (e) {
+      setToast(e instanceof Error ? e.message : "操作失败");
+      setTimeout(() => setToast(""), 2200);
+      setConfirmLeave(false);
+    } finally {
+      setLeaving(false);
+    }
+  };
+
   if (pageLoading) {
     return (
       <div className="flex min-h-dvh items-center justify-center bg-background">
@@ -620,6 +654,37 @@ export default function BlindboxRoomPage() {
         />
       )}
 
+      {/* Leave / Delete */}
+      {isMember && room && (
+        <motion.div
+          className="mt-12 w-full max-w-sm"
+          initial={{ opacity: 0 }}
+          animate={{ opacity: 1 }}
+          transition={{ delay: 0.5 }}
+        >
+          <button
+            onClick={handleLeaveOrDelete}
+            disabled={leaving}
+            className={`flex w-full items-center justify-center gap-2 rounded-xl py-2.5 text-xs font-medium transition-colors ${
+              confirmLeave
+                ? "bg-rose-600/15 text-rose-400 ring-1 ring-rose-500/30"
+                : "text-muted hover:text-rose-400/80"
+            }`}
+          >
+            {leaving ? (
+              <Loader2 size={13} className="animate-spin" />
+            ) : isCreator ? (
+              <Trash2 size={13} />
+            ) : (
+              <LogOut size={13} />
+            )}
+            {confirmLeave
+              ? isCreator ? "确认删除房间？所有想法将被清除" : "确认退出房间？"
+              : isCreator ? "删除房间" : "退出房间"}
+          </button>
+        </motion.div>
+      )}
+
       {/* Toast */}
       <AnimatePresence>
         {toast && (