feat(membership): replace purchase modal with membership page

frontend/src/components/rectification-agentic-chat.tsx

@@ -4,6 +4,7 @@ import { ArrowUp } from "lucide-react";
 import { useCallback, useEffect, useRef, useState } from "react";
 import { parseAgentReply } from "@/lib/agent-reply";
 import type { ChatMessage, ChatMessageView } from "@/lib/chat-message-view";
+import { membershipHref } from "@/lib/membership";
 import type { PublicLanguageModel } from "@/lib/public-models";
 import { ChatMessageRow } from "./chat-message-row";
 import { ModelSelector } from "./model-selector";
@@ -152,8 +153,11 @@ export function AgenticRectificationChat(props: AgenticRectificationChatProps) {
           onProfileIncomplete?.();
           return;
         }
-        if (response.status === 402) setError(`咨询点数不足：${message}`);
-        else if (response.status === 401) setError("请先登录。");
+        if (response.status === 402) {
+          window.location.assign(membershipHref("rectification"));
+          return;
+        }
+        if (response.status === 401) setError("请先登录。");
         else setError(message);
         return;
       }