perf(*): 创作工作台 - 优化首页按需加载与画布交互并修复历史迁移冲突

backend/internal/database/migrations.go

@@ -10,7 +10,7 @@ import (
 	"gorm.io/gorm"
 )
 
-const CurrentSchemaVersion int64 = 7
+const CurrentSchemaVersion int64 = 8
 
 const baselineSchemaChecksum = "sha256:open-ai-canvas-schema-v1-20260830"
 const schemaMigrationAppliedAtIndexChecksum = "sha256:schema-migrations-applied-at-index-v2-20260830"
@@ -19,6 +19,7 @@ const resourceUploadKeyChecksum = "sha256:resource-upload-key-v4-20260901"
 const paymentTopupChecksum = "sha256:payment-topup-v5-20260902"
 const resourcePlaybackChecksum = "sha256:resource-playback-v6-20260902"
 const assetLibraryFoldersChecksum = "sha256:asset-library-folders-v6-20260902"
+const logicalModelActiveCodeChecksum = "sha256:logical-model-active-code-v8-20260905"
 
 const postgresSchemaMigrationLockID int64 = 73123910420260830
 
@@ -52,6 +53,35 @@ var schemaMigrations = []migration{
 	{version: 5, name: "payment_topup", checksum: paymentTopupChecksum, apply: migrateSchemaV5},
 	{version: 6, name: "resource_playback_variant", checksum: resourcePlaybackChecksum, apply: migrateSchemaV6},
 	{version: 7, name: "asset_library_folders", checksum: assetLibraryFoldersChecksum, apply: migrateSchemaV7},
+	{version: 8, name: "logical_model_active_code", checksum: logicalModelActiveCodeChecksum, apply: migrateSchemaV8},
+}
+
+func migrationsForDatabase(db *gorm.DB) ([]migration, error) {
+	var applied schemaMigration
+	err := db.First(&applied, "version = ?", 6).Error
+	if errors.Is(err, gorm.ErrRecordNotFound) {
+		return schemaMigrations, nil
+	}
+	if err != nil {
+		return nil, fmt.Errorf("读取数据库迁移 6：%w", err)
+	}
+	if applied.Name != "asset_library_folders" {
+		return schemaMigrations, nil
+	}
+	legacy := migration{version: 6, name: "asset_library_folders", checksum: assetLibraryFoldersChecksum, apply: migrateSchemaV7}
+	if err := validateMigrationRecord(applied, legacy); err != nil {
+		return nil, err
+	}
+	plan := append([]migration(nil), schemaMigrations...)
+	for index, item := range plan {
+		switch item.version {
+		case 6:
+			plan[index] = legacy
+		case 7:
+			plan[index] = migration{version: 7, name: "resource_playback_variant", checksum: resourcePlaybackChecksum, apply: migrateSchemaV6}
+		}
+	}
+	return plan, nil
 }
 
 func migrateSchemaV2(tx *gorm.DB) error {
@@ -155,6 +185,19 @@ func migrateSchemaV7(tx *gorm.DB) error {
 	return nil
 }
 
+func migrateSchemaV8(tx *gorm.DB) error {
+	if !tx.Migrator().HasTable(&model.LogicalModel{}) {
+		return nil
+	}
+	if err := tx.Exec("DROP INDEX IF EXISTS idx_logical_models_code").Error; err != nil {
+		return fmt.Errorf("移除前台模型旧 code 唯一索引：%w", err)
+	}
+	if err := tx.Exec("CREATE UNIQUE INDEX idx_logical_models_code ON logical_models(code) WHERE archived_at IS NULL").Error; err != nil {
+		return fmt.Errorf("创建前台模型活动 code 唯一索引：%w", err)
+	}
+	return nil
+}
+
 func MigrateSchema(db *gorm.DB) error {
 	return db.Transaction(func(tx *gorm.DB) error {
 		if tx.Dialector.Name() == "postgres" {
@@ -165,7 +208,11 @@ func MigrateSchema(db *gorm.DB) error {
 		if err := tx.AutoMigrate(&schemaMigration{}); err != nil {
 			return fmt.Errorf("初始化数据库迁移记录：%w", err)
 		}
-		for _, item := range schemaMigrations {
+		plan, err := migrationsForDatabase(tx)
+		if err != nil {
+			return err
+		}
+		for _, item := range plan {
 			var applied schemaMigration
 			err := tx.First(&applied, "version = ?", item.version).Error
 			if err == nil {
@@ -208,7 +255,11 @@ func ReadSchemaStatus(db *gorm.DB) (SchemaStatus, error) {
 }
 
 func validateMigrationRecords(db *gorm.DB) error {
-	for _, item := range schemaMigrations {
+	plan, err := migrationsForDatabase(db)
+	if err != nil {
+		return err
+	}
+	for _, item := range plan {
 		var applied schemaMigration
 		if err := db.First(&applied, "version = ?", item.version).Error; err != nil {
 			if errors.Is(err, gorm.ErrRecordNotFound) {