feat: activity log backend foundation

internal/infrastructure/persistence/models/auditSettingsModel.go

@@ -0,0 +1,10 @@
+package models
+
+import "time"
+
+type AuditSettings struct {
+	ID                 uint32 `gorm:"primaryKey"`
+	RetentionDays      int    `gorm:"not null"`
+	LastCleanupAt      *time.Time
+	LastCleanupRemoved int `gorm:"not null"`
+}