Implement health check for deploy. Make version endpoint to return revision if not set

internal/service/database/db_service.go

@@ -109,3 +109,17 @@ func (d *dbService) UpdatePayoutByPayoutID(payoutId string, updateModel orm.Payo
 	p := d.getParams(opts...)
 	return gorm.G[orm.Payout](d.db).Where("payout_id = ?", payoutId).Updates(p.ctx, updateModel)
 }
+
+// HealthCheck implements [Service].
+func (d *dbService) HealthCheck() error {
+	if d.db == nil {
+		return errors.New("database connection is nil")
+	}
+
+	db, err := d.db.DB()
+	if err != nil {
+		return err
+	}
+
+	return db.Ping()
+}