added filtering and cronjob soft delete for old events

backend/repositories/EventRepository.go

@@ -19,6 +19,7 @@ import (
 type EventRepository interface {
 	Save(event *models.Event) error
 	FindAll() ([]models.Event, error)
+	SoftDeleteEndedBefore(cutoffDate string) (int64, error)
 }
 
 type eventRepository struct {
@@ -101,6 +102,18 @@ func (r *eventRepository) FindAll() ([]models.Event, error) {
 	return events, result.Error
 }
 
+// SoftDeleteEndedBefore marks events whose end_date is before cutoffDate
+// (an exclusive "YYYY-MM-DD" boundary, the same lexicographic string
+// comparison the frontend uses for its own date filtering) as deleted.
+// .Delete() on a gorm.Model sets deleted_at rather than removing the row,
+// consistent with how the frontend already treats soft-deleted events.
+// Events with a blank end_date are left alone — there's nothing to
+// compare, so leaving them is safer than guessing they're stale.
+func (r *eventRepository) SoftDeleteEndedBefore(cutoffDate string) (int64, error) {
+	result := r.db.Where("end_date <> '' AND end_date < ?", cutoffDate).Delete(&models.Event{})
+	return result.RowsAffected, result.Error
+}
+
 func (r *eventRepository) saveMediaFile(filename string, url string, mediaType string, extension string) error {
 	mediaFilePath := fmt.Sprintf("./public/storage/%s/%s%s", strings.ToLower(mediaType), filename, extension)