feat(holiday-system): add holiday population functionality and API integration

- Implemented a new API endpoint to populate country holidays in the database.
- Enhanced the HolidayController to handle holiday population logic for multiple countries.
- Updated the holiday API router to include the new populate endpoint.
- Added a service method in the frontend to trigger holiday population.
- Integrated a button in the admin center overview for easy access to populate holidays.
- Improved error handling and user feedback during the holiday population process.

worklenz-frontend/src/api/holiday/holiday.api.service.ts

@@ -65,4 +65,10 @@ export const holidayApiService = {
     const response = await apiClient.get<IServerResponse<IHolidayCalendarEvent[]>>(`${rootUrl}/calendar?year=${year}&month=${month}`);
     return response.data;
   },
+
+  // Populate holidays
+  populateCountryHolidays: async (): Promise<IServerResponse<any>> => {
+    const response = await apiClient.post<IServerResponse<any>>(`${rootUrl}/populate`);
+    return response.data;
+  },
 }; 

worklenz-frontend/src/pages/admin-center/overview/overview.tsx

@@ -1,6 +1,6 @@
-import { EditOutlined, MailOutlined, PhoneOutlined } from '@ant-design/icons';
+import { EditOutlined, MailOutlined, PhoneOutlined, DatabaseOutlined } from '@ant-design/icons';
 import { PageHeader } from '@ant-design/pro-components';
-import { Button, Card, Input, Space, Tooltip, Typography } from 'antd';
+import { Button, Card, Input, Space, Tooltip, Typography, message } from 'antd';
 import React, { useEffect, useState } from 'react';
 import OrganizationAdminsTable from '@/components/admin-center/overview/organization-admins-table/organization-admins-table';
 import { useAppSelector } from '@/hooks/useAppSelector';
@@ -10,6 +10,7 @@ import OrganizationName from '@/components/admin-center/overview/organization-na
 import OrganizationOwner from '@/components/admin-center/overview/organization-owner/organization-owner';
 import HolidayCalendar from '@/components/admin-center/overview/holiday-calendar/holiday-calendar';
 import { adminCenterApiService } from '@/api/admin-center/admin-center.api.service';
+import { holidayApiService } from '@/api/holiday/holiday.api.service';
 import { IOrganization, IOrganizationAdmin } from '@/types/admin-center/admin-center.types';
 import logger from '@/utils/errorLogger';
 
@@ -19,6 +20,7 @@ const Overview: React.FC = () => {
   const [organization, setOrganization] = useState<IOrganization | null>(null);
   const [organizationAdmins, setOrganizationAdmins] = useState<IOrganizationAdmin[] | null>(null);
   const [loadingAdmins, setLoadingAdmins] = useState(false);
+  const [populatingHolidays, setPopulatingHolidays] = useState(false);
 
   const themeMode = useAppSelector((state: RootState) => state.themeReducer.mode);
   const { t } = useTranslation('admin-center/overview');
@@ -48,6 +50,21 @@ const Overview: React.FC = () => {
     }
   };
 
+  const handlePopulateHolidays = async () => {
+    setPopulatingHolidays(true);
+    try {
+      const res = await holidayApiService.populateCountryHolidays();
+      if (res.done) {
+        message.success(`Successfully populated ${res.body.total_populated} holidays`);
+      }
+    } catch (error) {
+      logger.error('Error populating holidays', error);
+      message.error('Failed to populate holidays');
+    } finally {
+      setPopulatingHolidays(false);
+    }
+  };
+
   useEffect(() => {
     getOrganizationDetails();
     getOrganizationAdmins();
@@ -55,7 +72,20 @@ const Overview: React.FC = () => {
 
   return (
     <div style={{ width: '100%' }}>
-      <PageHeader title={<span>{t('overview')}</span>} style={{ padding: '16px 0' }} />
+      <PageHeader 
+        title={<span>{t('overview')}</span>} 
+        style={{ padding: '16px 0' }}
+        extra={[
+          <Button
+            key="populate-holidays"
+            icon={<DatabaseOutlined />}
+            onClick={handlePopulateHolidays}
+            loading={populatingHolidays}
+          >
+            Populate Holidays Database
+          </Button>
+        ]}
+      />
 
       <Space direction="vertical" style={{ width: '100%' }} size={22}>
         <OrganizationName