[优化] 重构数据库迁移逻辑，整合遗留和Goose迁移处理

openflare_server/model/main.go

@@ -54,12 +54,23 @@ func registeredModels() []any {
 	}
 }
 
-func schemaMetadataModels() []any {
+func currentSchemaMetadataModels() []any {
+	return nil
+}
+
+func legacySchemaMetadataModels() []any {
 	return []any{
 		&DatabaseSchemaVersion{},
 	}
 }
 
+func schemaMetadataModels() []any {
+	models := make([]any, 0, len(currentSchemaMetadataModels())+len(legacySchemaMetadataModels()))
+	models = append(models, currentSchemaMetadataModels()...)
+	models = append(models, legacySchemaMetadataModels()...)
+	return models
+}
+
 func buildDBModels() ([]dbModel, error) {
 	models := registeredModels()
 	result := make([]dbModel, 0, len(models))