added structs functions

backend/models/model_game_system.go

@@ -1,5 +1,7 @@
 package models
 
+import "bamort/database"
+
 type GameSystem struct {
 	ID          uint   `gorm:"primaryKey"`
 	Code        string `gorm:"uniqueIndex;size:100;not null"`
@@ -14,3 +16,15 @@ type GameSystem struct {
 func (GameSystem) TableName() string {
 	return "game_systems"
 }
+
+func (gs *GameSystem) FirstByCode(code string) error {
+	return database.DB.First(gs, "code = ?", code).Error
+}
+
+func (gs *GameSystem) GetDefault() error {
+	return database.DB.First(gs, "is_active = ?", true).Error
+}
+
+func (gs *GameSystem) FirstByName(name string) error {
+	return database.DB.First(gs, "name = ?", name).Error
+}