♻️ 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/sqlite_impl.go

@@ -78,33 +78,7 @@ func (s *SQLiteDB) Query(query string) ([]map[string]interface{}, []string, erro
 		return nil, nil, err
 	}
 	defer rows.Close()
-
-	columns, err := rows.Columns()
-	if err != nil {
-		return nil, nil, err
-	}
-
-	var resultData []map[string]interface{}
-
-	for rows.Next() {
-		values := make([]interface{}, len(columns))
-		valuePtrs := make([]interface{}, len(columns))
-		for i := range columns {
-			valuePtrs[i] = &values[i]
-		}
-
-		if err := rows.Scan(valuePtrs...); err != nil {
-			continue
-		}
-
-		entry := make(map[string]interface{})
-		for i, col := range columns {
-			entry[col] = normalizeQueryValue(values[i])
-		}
-		resultData = append(resultData, entry)
-	}
-
-	return resultData, columns, nil
+	return scanRows(rows)
 }
 
 func (s *SQLiteDB) ExecContext(ctx context.Context, query string) (int64, error) {