core: fix OI mode contest score leak (#860)

Co-authored-by: undefined <i@undefined.moe>

packages/hydrooj/src/handler/contest.ts

@@ -222,7 +222,7 @@ export class ContestProblemListHandler extends ContestDetailBaseHandler {
             contest.getMultiClarification(domainId, tid, this.user._id),
         ]);
         this.response.body = {
-            pdict, psdict: {}, udict, rdict: {}, tdoc: this.tdoc, tsdoc: this.tsdoc, tcdocs,
+            pdict, psdict: {}, udict, rdict: {}, tdoc: this.tdoc, tcdocs,
         };
         this.response.template = 'contest_problemlist.html';
         this.response.body.showScore = Object.values(this.tdoc.score || {}).some((i) => i && i !== 100);
@@ -231,6 +231,7 @@ export class ContestProblemListHandler extends ContestDetailBaseHandler {
             await contest.setStatus(domainId, tid, this.user._id, { startAt: new Date() });
             this.tsdoc.startAt = new Date();
         }
+        this.response.body.tsdoc = pick(this.tsdoc, ['attend', 'startAt', ...(this.tdoc.duration ? ['endAt'] : [])]);
         this.response.body.psdict = this.tsdoc.detail || {};
         const psdocs: any[] = Object.values(this.response.body.psdict);
         const canViewRecord = contest.canShowSelfRecord.call(this, this.tdoc);