Fix calendar month value type to use Date instead of string

Fixed invalid date error when selecting month:
- Changed valueYear (string) to valueMonth (Date) state
- Set valueMonth using moment().toDate() for all calendar types
- Parse startMonth, endMonth, singleMonth with moment and convert to Date
- Calendar component now receives proper Date object instead of year string
- This fixes the "Invalid date" error and prevents error cascade

Changes:
- useState<string> → useState<Date | undefined>
- setValueYear(year) → setValueMonth(moment().toDate())
- Calendar value prop now receives Date object

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

src/shared/ui/calendar/nice-calendar-month.tsx

@@ -29,7 +29,7 @@ const NiceCalendarMonth = ({
   const { i18n } = useTranslation();
   const currentLocale = i18n.language || 'en';
 
-  const [valueYear, setValueYear] = useState<string>();
+  const [valueMonth, setValueMonth] = useState<Date | undefined>();
   const [minMonth, setMinMonth] = useState<Date | undefined>();
   const [maxMonth, setMaxMonth] = useState<Date | undefined>();
   const onChangeToMonth = (selectedMonth: any) => {
@@ -50,7 +50,12 @@ const NiceCalendarMonth = ({
           setMaxMonth(endDate.toDate());
         }
       }
-      setValueYear(startMonth?.substring(0, 4));
+      if (startMonth) {
+        const startDate = moment(startMonth, ['YYYY.MM', 'YYYYMM'], true);
+        if (startDate.isValid()) {
+          setValueMonth(startDate.toDate());
+        }
+      }
     }
     else if(calendarType === CalendarType.End){
       if(!!startMonth){
@@ -61,10 +66,20 @@ const NiceCalendarMonth = ({
         }
       }
       setMaxMonth(new Date());
-      setValueYear(endMonth?.substring(0, 4));
+      if (endMonth) {
+        const endDate = moment(endMonth, ['YYYY.MM', 'YYYYMM'], true);
+        if (endDate.isValid()) {
+          setValueMonth(endDate.toDate());
+        }
+      }
     }
     else if(calendarType === CalendarType.Single){
-      setValueYear(singleMonth?.substring(0, 4));
+      if (singleMonth) {
+        const singleDate = moment(singleMonth, ['YYYY.MM', 'YYYYMM'], true);
+        if (singleDate.isValid()) {
+          setValueMonth(singleDate.toDate());
+        }
+      }
     }
   };
   
@@ -115,7 +130,7 @@ const NiceCalendarMonth = ({
             minDate={ minMonth }
             maxDate={ maxMonth }
             onClickMonth={ onChangeToMonth }
-            value={ valueYear }
+            value={ valueMonth }
             formatMonthYear={ formatMonthYear }
             formatYear= { formatYear }
             formatMonth={ formmatMonth }