feat: 完善扫描器、exec 及 schema 相关功能

- exec/scanner: 用 *interface{} 替换 **json.RawMessage 扫描目标，兼容 DuckDB 返回 map[string]interface{} 的场景；新增 toJSONRawMessage 转换函数
- exec/scanner: ScanVal 支持结构体指针，通过 JSON 中间层转换（DuckDB STRUCT 列）
- exec/scanner: 将 *sql.RawBytes 和 *[]byte 的处理从 ScanValContext 移入 scanner.ScanVal
- exec/query_executor: 简化 ScanValContext，移除私有 scan 方法
- exec: 补充 scanner 级别 ScanVal 测试用例
- internal/util/reflect: 重写 SafeSetVarValue，修复非指针 src 及 nil 指针字段的 panic
- internal/util/column_map: 恢复非匿名带标签结构体字段的展开逻辑
- schema: 新增 vector 列类型支持
- engine: 补充 DuckDB 相关配置
- dialect/sqlite3/vtab: 完善虚拟表适配器
- 各方言测试改用 sqlmock 虚拟连接

schema/dialect/mysql/mysql_test.go

@@ -1,15 +1,13 @@
 package mysql_test
 
 import (
-	"os"
 	"testing"
 
 	"git.fsdpf.net/go/db"
 	"git.fsdpf.net/go/db/engine"
 	"git.fsdpf.net/go/db/schema"
+	sqlmock "github.com/DATA-DOG/go-sqlmock"
 	"github.com/stretchr/testify/suite"
-
-	_ "github.com/go-sql-driver/mysql"
 )
 
 type mysqlTest struct {
@@ -17,42 +15,28 @@ type mysqlTest struct {
 	schema schema.Schema
 }
 
-var (
-	tableName = "entry"
-
-	dropTable = "DROP TABLE IF EXISTS `entry`;"
-
-	createTable = "CREATE TABLE IF NOT EXISTS `entry` (" +
-		"`id` INT NOT NULL AUTO_INCREMENT ," +
-		"`int` INT NOT NULL UNIQUE," +
-		"`float` FLOAT NOT NULL ," +
-		"`string` VARCHAR(255) NOT NULL ," +
-		"`time` DATETIME NOT NULL ," +
-		"`bool` TINYINT NOT NULL ," +
-		"`bytes` BLOB NOT NULL ," +
-		"PRIMARY KEY (`id`) );"
-)
+var tableName = "entry"
 
 func TestMysqlSuite(t *testing.T) {
 	suite.Run(t, new(mysqlTest))
 }
 
 func (t *mysqlTest) SetupSuite() {
-	db := engine.Open(map[string]engine.DBConfig{
-		"test-mysql": engine.NewDBConfig("mysql",
-			engine.WithHost(os.Getenv("MYSQL_HOST")),
-			engine.WithPort(os.Getenv("MYSQL_PORT")),
-			engine.WithDatabase(os.Getenv("MYSQL_DB")),
-			engine.WithUsername(os.Getenv("MYSQL_USER")),
-			engine.WithPassword(os.Getenv("MYSQL_PASSWD")),
-			engine.WithParseTime(true),
-		),
+	mockDB, mock, _ := sqlmock.New()
+
+	mock.ExpectQuery("SELECT.*column_name.*columns").
+		WillReturnRows(sqlmock.NewRows([]string{"column_name"}).
+			AddRow("id").AddRow("int").AddRow("float").
+			AddRow("string").AddRow("time").AddRow("bool").AddRow("bytes"))
+
+	mock.ExpectQuery("SELECT.*COUNT.*tables").
+		WillReturnRows(sqlmock.NewRows([]string{"count"}).AddRow(1))
+
+	conn := engine.Mock(map[string]engine.MockDBConfig{
+		"test-mysql": {Driver: "mysql", Mock: mockDB},
 	}).Connection("test-mysql")
 
-	t.schema = schema.GetSchemaDialect(db)
-
-	// db.Exec(dropTable)
-	db.Exec(createTable)
+	t.schema = schema.GetSchemaDialect(conn)
 }
 
 func (t *mysqlTest) TestGetColumnListing() {
@@ -84,7 +68,7 @@ func (t *mysqlTest) TestCompileCreate() {
 	sql := t.schema.CompileCreate(bp)
 
 	t.Equal([]string{
-		"CREATE TABLE `users` (\n" +
+		"CREATE TABLE IF NOT EXISTS `users` (\n" +
 			"`id` bigint(20) UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY COMMENT 'ID',\n" +
 			"`enabled` tinyint(1) NOT NULL DEFAULT '1' COMMENT '是否有效',\n" +
 			"`created_user` char(36) NOT NULL DEFAULT '00000000-0000-0000-0000-000000000000' COMMENT '创建者',\n" +
@@ -125,11 +109,13 @@ func (t *mysqlTest) TestCompileChange() {
 	bp.String("name", 50).Change("username")
 	bp.SmallInteger("age").Default("19").Comment("年龄").Change()
 
-	sql := "ALTER TABLE `users`\n" +
-		"CHANGE COLUMN `name` `username` varchar(50) NOT NULL,\n" +
-		"CHANGE COLUMN `age` `age` smallint(4) NOT NULL DEFAULT '19' COMMENT '年龄';"
+	sql := t.schema.CompileChange(bp)
 
-	t.Equal(t.schema.CompileChange(bp), sql)
+	t.Equal([]string{
+		"ALTER TABLE `users`\n" +
+			"CHANGE COLUMN `name` `username` varchar(50) NOT NULL,\n" +
+			"CHANGE COLUMN `age` `age` smallint(4) NOT NULL DEFAULT '19' COMMENT '年龄'",
+	}, sql)
 
 	t.T().Log(sql)
 }
@@ -189,4 +175,19 @@ func (t *mysqlTest) TestCompileRename() {
 	t.T().Log(sql)
 }
 
+// 添加虚拟生成列
+func (t *mysqlTest) TestCompileAddVirtualColumn() {
+	bp := schema.NewBlueprint("user_assets")
+	bp.String("file_url", 512).VirtualAs("CONCAT('/api/user-asset-raw/', file)").Comment("文件访问URL")
+
+	sql := t.schema.CompileAdd(bp)
+
+	t.Equal([]string{
+		"ALTER TABLE `user_assets`\n" +
+			"ADD COLUMN `file_url` varchar(512) GENERATED ALWAYS AS (CONCAT('/api/user-asset-raw/', file)) VIRTUAL COMMENT '文件访问URL'",
+	}, sql)
+
+	t.T().Log(sql)
+}
+
 // 修改表备注