fix: Use date-fns parse with an explicit format string instead of parseISO for more robust date string conversion.

Author: peterlipt

services/conference.service.ts

@@ -33,7 +33,7 @@ export class ConferenceService {
     }
     const d = new Date(timestamp);
     if (isNaN(d.getTime())) return 'n/a';
-    
+
     try {
       return format(d, 'HH:mm');
     } catch {

utils/date.utils.ts

@@ -1,4 +1,4 @@
-import { format, isSameDay, parseISO } from 'date-fns';
+import { format, isSameDay, parse } from 'date-fns';
 import { hu } from 'date-fns/locale';
 
 export function formatHu(date: Date): string {
@@ -11,7 +11,7 @@ export function isConferenceDay(): boolean {
     return true;
   }
 
-  const targetDate = parseISO(targetDateStr);
+  const targetDate = parse(targetDateStr, 'yyyy-MM-dd', new Date());
   if (isNaN(targetDate.getTime())) {
     return true;
   }