feat(recurring-tasks): implement recurring tasks service with timezone support and notifications

- Added a new service for managing recurring tasks, allowing configuration of task schedules with timezone support.
- Introduced job queues for processing recurring tasks and handling task creation in bulk.
- Implemented notification system to alert users about newly created recurring tasks, including email and in-app notifications.
- Enhanced database schema with new tables for notifications and audit logs to track recurring task operations.
- Updated frontend components to support timezone selection and manage excluded dates for recurring tasks.
- Refactored existing code to integrate new features and improve overall task management experience.

worklenz-backend/src/config/recurring-tasks-config.ts

@@ -0,0 +1,57 @@
+export interface RecurringTasksConfig {
+  enabled: boolean;
+  mode: 'cron' | 'queue';
+  cronInterval: string;
+  redisConfig: {
+    host: string;
+    port: number;
+    password?: string;
+    db: number;
+  };
+  queueOptions: {
+    maxConcurrency: number;
+    retryAttempts: number;
+    retryDelay: number;
+  };
+  notifications: {
+    enabled: boolean;
+    email: boolean;
+    push: boolean;
+    inApp: boolean;
+  };
+  auditLog: {
+    enabled: boolean;
+    retentionDays: number;
+  };
+}
+
+export const recurringTasksConfig: RecurringTasksConfig = {
+  enabled: process.env.RECURRING_TASKS_ENABLED !== 'false',
+  mode: (process.env.RECURRING_TASKS_MODE as 'cron' | 'queue') || 'cron',
+  cronInterval: process.env.RECURRING_JOBS_INTERVAL || '0 * * * *',
+  
+  redisConfig: {
+    host: process.env.REDIS_HOST || 'localhost',
+    port: parseInt(process.env.REDIS_PORT || '6379'),
+    password: process.env.REDIS_PASSWORD,
+    db: parseInt(process.env.REDIS_DB || '0'),
+  },
+  
+  queueOptions: {
+    maxConcurrency: parseInt(process.env.RECURRING_TASKS_MAX_CONCURRENCY || '5'),
+    retryAttempts: parseInt(process.env.RECURRING_TASKS_RETRY_ATTEMPTS || '3'),
+    retryDelay: parseInt(process.env.RECURRING_TASKS_RETRY_DELAY || '2000'),
+  },
+  
+  notifications: {
+    enabled: process.env.RECURRING_TASKS_NOTIFICATIONS_ENABLED !== 'false',
+    email: process.env.RECURRING_TASKS_EMAIL_NOTIFICATIONS !== 'false',
+    push: process.env.RECURRING_TASKS_PUSH_NOTIFICATIONS !== 'false',
+    inApp: process.env.RECURRING_TASKS_IN_APP_NOTIFICATIONS !== 'false',
+  },
+  
+  auditLog: {
+    enabled: process.env.RECURRING_TASKS_AUDIT_LOG_ENABLED !== 'false',
+    retentionDays: parseInt(process.env.RECURRING_TASKS_AUDIT_RETENTION_DAYS || '90'),
+  },
+};