feat: 添加分页功能和缓存管理，优化问答记录展示

server/api/search.ts

@@ -1,4 +1,6 @@
 // server/api/search.ts - OCS AnswererWrapper 兼容搜索接口
+import { createHash } from "node:crypto";
+
 import {
   getQuery,
   type H3Event,
@@ -16,11 +18,10 @@ import {
   type SearchParams
 } from "~~/server/utils/answer";
 import { getAuthSession } from "~~/server/utils/auth";
-import { answerCache } from "~~/server/utils/cache";
 import { prisma } from "~~/server/utils/db";
 import { createApiLogger, toSafeLogError } from "~~/server/utils/logging";
 import { askAnswerStream } from "~~/server/utils/openai";
-import { addQaRecord } from "~~/server/utils/runtimeState";
+import { addQaRecord, lookupCachedAnswer } from "~~/server/utils/runtimeState";
 
 /**
  * 把 query/body/form 中的值统一转成字符串
@@ -138,17 +139,25 @@ export default defineEventHandler(async (event) => {
 
     // 鉴权：优先 session（浏览器登录），无 session 则用 body.token 查 apiToken
     // OCS 油猴脚本跨域无法携带 cookie，需在 body 中传入用户自己的 apiToken
+    // 同时取出 cacheClearedAt，用于 DB 缓存过滤
     let userId: string | null = null;
+    let cacheClearedAt: Date | null = null;
 
     const session = await getAuthSession(event);
     if (session) {
       userId = session.user.id;
+      const userData = await prisma.user.findUnique({
+        where: { id: userId },
+        select: { cacheClearedAt: true }
+      });
+      cacheClearedAt = userData?.cacheClearedAt ?? null;
     } else if (params.token) {
       const user = await prisma.user.findUnique({
         where: { apiToken: params.token },
-        select: { id: true }
+        select: { id: true, cacheClearedAt: true }
       });
       userId = user?.id ?? null;
+      cacheClearedAt = user?.cacheClearedAt ?? null;
     }
 
     if (!userId) {
@@ -167,12 +176,12 @@ export default defineEventHandler(async (event) => {
       return createOcsErrorResponse("未提供问题内容");
     }
 
-    // 缓存 key 包含题目、题型和选项；同题不同选项不能共用答案
-    const cachedAnswer = answerCache?.get(
-      params.title,
-      params.type,
-      params.options
-    );
+    // 计算缓存 key：题目+题型+选项的 MD5；同题不同选项不能共用答案
+    const hash = createHash("md5")
+      .update(`${params.title}|${params.type}|${params.options}`, "utf8")
+      .digest("hex");
+
+    const cachedAnswer = await lookupCachedAnswer(userId, hash, cacheClearedAt);
 
     if (cachedAnswer) {
       logger.info("cache_hit");
@@ -191,19 +200,14 @@ export default defineEventHandler(async (event) => {
     });
     const processedAnswer = extractAnswer(streamResult.answer, params.type);
 
-    // 先缓存再记录；这两步失败风险很低，且都是内存操作，不会阻塞主链路
-    answerCache?.set(
-      params.title,
-      processedAnswer,
-      params.type,
-      params.options
-    );
+    // 写入 DB 记录（带 hash）；记录本身即为后续缓存查询的来源
     await addQaRecord({
       userId,
       question: params.title,
       type: params.type,
       options: params.options,
-      answer: processedAnswer
+      answer: processedAnswer,
+      hash
     });
 
     logger.info("finish_success", {