core: search: remove duplicate

packages/hydrooj/package.json

@@ -1,6 +1,6 @@
 {
     "name": "hydrooj",
-    "version": "2.28.39",
+    "version": "2.28.40",
     "bin": "bin/hydrooj.js",
     "main": "dist/loader.js",
     "typings": "dist/loader.d.ts",

packages/hydrooj/src/handler/problem.ts

@@ -100,7 +100,7 @@ export class ProblemMainHandler extends ProblemHandler {
         if (sort) pdocs = pdocs.sort((a, b) => sort.indexOf(a.docId) - sort.indexOf(b.docId));
         if (q && +q) {
             const pdoc = await problem.get(domainId, +q, problem.PROJECTION_LIST);
-            if (pdoc) pdocs.unshift(pdoc);
+            if (pdoc) pdocs.filter((doc) => doc.docId !== pdoc.docId).unshift(pdoc);
         }
         if (this.user.hasPriv(PRIV.PRIV_USER_PROFILE)) {
             psdict = await problem.getListStatus(