♻️ refactor(database/ssh): SSH隧道架构重构与多数据源适配

- 架构升级：从driver专属拨号器改为通用本地端口转发模式
  - 并发安全：sync.Once保护Close操作,RWMutex保护状态访问,双向errc等待
  - 连接池化：GetOrCreateLocalForwarder/GetOrCreateSSHClient实现缓存复用
  - SQL安全：kingbase_impl.go引入esc函数,防止双引号注入(""ldf_server""问题)
  - Schema动态化：三级fallback(schema.table解析→dbName参数→current_schema())
  - 代码复用：scanRows统一行扫描逻辑,normalizeQueryValueWithDBType增强类型处理
  Close #40

internal/db/query_value.go

@@ -2,6 +2,8 @@ package db
 
 import (
 	"encoding/hex"
+	"fmt"
+	"strings"
 	"unicode"
 	"unicode/utf8"
 )
@@ -9,13 +11,17 @@ import (
 // normalizeQueryValue normalizes driver-returned values for UI/JSON transport.
 // 当前主要处理 []byte：如果是可读文本则转为 string，否则转为十六进制字符串，避免前端出现“空白值”。
 func normalizeQueryValue(v interface{}) interface{} {
+	return normalizeQueryValueWithDBType(v, "")
+}
+
+func normalizeQueryValueWithDBType(v interface{}, databaseTypeName string) interface{} {
 	if b, ok := v.([]byte); ok {
-		return bytesToReadableString(b)
+		return bytesToDisplayValue(b, databaseTypeName)
 	}
 	return v
 }
 
-func bytesToReadableString(b []byte) interface{} {
+func bytesToDisplayValue(b []byte, databaseTypeName string) interface{} {
 	if b == nil {
 		return nil
 	}
@@ -23,6 +29,18 @@ func bytesToReadableString(b []byte) interface{} {
 		return ""
 	}
 
+	dbType := strings.ToUpper(strings.TrimSpace(databaseTypeName))
+	if isBitLikeDBType(dbType) {
+		if u, ok := bytesToUint64(b); ok {
+			// JS number precision is limited; keep large bitmasks as string.
+			const maxSafeInteger = 9007199254740991 // 2^53 - 1
+			if u <= maxSafeInteger {
+				return int64(u)
+			}
+			return fmt.Sprintf("%d", u)
+		}
+	}
+
 	if utf8.Valid(b) {
 		s := string(b)
 		if isMostlyPrintable(s) {
@@ -30,9 +48,47 @@ func bytesToReadableString(b []byte) interface{} {
 		}
 	}
 
+	// Fallback: some drivers return BIT(1) as []byte{0} / []byte{1} without type info.
+	if dbType == "" && len(b) == 1 && (b[0] == 0 || b[0] == 1) {
+		return int64(b[0])
+	}
+
+	return bytesToReadableString(b)
+}
+
+func bytesToReadableString(b []byte) interface{} {
+	if b == nil {
+		return nil
+	}
+	if len(b) == 0 {
+		return ""
+	}
 	return "0x" + hex.EncodeToString(b)
 }
 
+func isBitLikeDBType(typeName string) bool {
+	if typeName == "" {
+		return false
+	}
+	switch typeName {
+	case "BIT", "VARBIT":
+		return true
+	default:
+	}
+	return strings.HasPrefix(typeName, "BIT")
+}
+
+func bytesToUint64(b []byte) (uint64, bool) {
+	if len(b) == 0 || len(b) > 8 {
+		return 0, false
+	}
+	var u uint64
+	for _, v := range b {
+		u = (u << 8) | uint64(v)
+	}
+	return u, true
+}
+
 func isMostlyPrintable(s string) bool {
 	if s == "" {
 		return true