feat: Integrate data retention service

- Implemented the data retention service in Go (service-operation) that manages cleanup of old records based on configured retention periods. The service runs once per day to ensure outdated data is removed automatically.

server/service-operation/data-retention/scheduler.go

@@ -0,0 +1,63 @@
+package dataretention
+
+import (
+	"service-operation/pocketbase"
+	"time"
+)
+
+// Scheduler handles periodic data retention cleanup
+type Scheduler struct {
+	service  *Service
+	interval time.Duration
+	stopChan chan bool
+}
+
+// NewScheduler creates a new cleanup scheduler
+func NewScheduler(pbClient *pocketbase.PocketBaseClient, interval time.Duration) *Scheduler {
+	return &Scheduler{
+		service:  NewService(pbClient),
+		interval: interval,
+		stopChan: make(chan bool),
+	}
+}
+
+// Start begins the periodic cleanup process
+func (s *Scheduler) Start() {
+	// log.Printf("Starting data retention scheduler with interval: %v", s.interval)
+	
+	ticker := time.NewTicker(s.interval)
+	defer ticker.Stop()
+
+	// Run initial cleanup
+	go func() {
+		if err := s.service.ScheduleCleanup(); err != nil {
+			// log.Printf("Initial cleanup failed: %v", err)
+		}
+	}()
+
+	for {
+		select {
+		case <-ticker.C:
+			go func() {
+				if err := s.service.ScheduleCleanup(); err != nil {
+					// log.Printf("Scheduled cleanup failed: %v", err)
+				}
+			}()
+		case <-s.stopChan:
+			// log.Println("Data retention scheduler stopped")
+			return
+		}
+	}
+}
+
+// Stop stops the scheduler
+func (s *Scheduler) Stop() {
+	// log.Println("Stopping data retention scheduler...")
+	s.stopChan <- true
+}
+
+// RunOnce executes cleanup immediately (for manual triggers)
+func (s *Scheduler) RunOnce() (*CleanupSummary, error) {
+	// log.Println("Running manual data retention cleanup...")
+	return s.service.CleanupOldRecords()
+}