Send dates instead of date with time / timezone

Author: Allaoua Benchikh

frontend/src/components/ChatSettings/DatePickerInput.tsx

@@ -24,7 +24,8 @@ import { InputStateHandler } from './InputStateHandler';
 const parseDate = (dateStr: string | undefined | null): Date | undefined => {
   if (!dateStr) return undefined;
   try {
-    const date = new Date(dateStr);
+    // Append T00:00:00 to force local timezone parsing instead of UTC
+    const date = new Date(dateStr + 'T00:00:00');
     // Check if date is valid (Invalid Date has NaN time)
     if (isNaN(date.getTime())) {
       console.warn(`Invalid date string provided: "${dateStr}"`);
@@ -38,7 +39,10 @@ const parseDate = (dateStr: string | undefined | null): Date | undefined => {
 
 const formatDateValue = (date: Date | undefined): string | undefined => {
   if (!date) return undefined;
-  return date.toISOString();
+  const year = date.getFullYear();
+  const month = String(date.getMonth() + 1).padStart(2, '0');
+  const day = String(date.getDate()).padStart(2, '0');
+  return `${year}-${month}-${day}`;
 };
 
 const formatRangeValue = (