♻️ refactor(全局): 统一错误消息中文化，补充 godoc 与测试，修复横向滚动和 Vite 代理

错误消息中文化:
- 19 个驱动实现文件中 connection not open / table name required 等英文消息替换为中文
- methods_file.go / methods_db.go / methods_driver.go 英文消息中文化
- 前端 App/Sidebar/DataGrid/ConnectionModal/DriverManagerModal 同步替换 "Cancelled" → "已取消"

文档与测试:
- database.go Database/BatchApplier 接口、types.go 12 个类型、driver_support.go 导出函数补充中文 godoc
- 新增 logger_test.go（ErrorChain 5 个用例）和 methods_db_conn_test.go（连接管理 7 个用例）

Bug 修复:
- DataGrid: 将 liveTargets 空检查移至非虚拟路径，修复外部横向滚动条拖动时内容不跟随
- vite.config.ts: server.host 指定 127.0.0.1，修复 IPv6 回环被拦截导致 Wails 代理 502

基础设施:
- .gitignore 新增 .gemini/ 规则，tmpclaude-* 改为 **/tmpclaude-* 覆盖子目录

internal/db/oracle_impl.go

@@ -135,7 +135,7 @@ func (o *OracleDB) Close() error {
 
 func (o *OracleDB) Ping() error {
 	if o.conn == nil {
-		return fmt.Errorf("connection not open")
+		return fmt.Errorf("连接未打开")
 	}
 	timeout := o.pingTimeout
 	if timeout <= 0 {
@@ -148,7 +148,7 @@ func (o *OracleDB) Ping() error {
 
 func (o *OracleDB) QueryContext(ctx context.Context, query string) ([]map[string]interface{}, []string, error) {
 	if o.conn == nil {
-		return nil, nil, fmt.Errorf("connection not open")
+		return nil, nil, fmt.Errorf("连接未打开")
 	}
 
 	rows, err := o.conn.QueryContext(ctx, query)
@@ -162,7 +162,7 @@ func (o *OracleDB) QueryContext(ctx context.Context, query string) ([]map[string
 
 func (o *OracleDB) Query(query string) ([]map[string]interface{}, []string, error) {
 	if o.conn == nil {
-		return nil, nil, fmt.Errorf("connection not open")
+		return nil, nil, fmt.Errorf("连接未打开")
 	}
 
 	rows, err := o.conn.Query(query)
@@ -175,7 +175,7 @@ func (o *OracleDB) Query(query string) ([]map[string]interface{}, []string, erro
 
 func (o *OracleDB) ExecContext(ctx context.Context, query string) (int64, error) {
 	if o.conn == nil {
-		return 0, fmt.Errorf("connection not open")
+		return 0, fmt.Errorf("连接未打开")
 	}
 	res, err := o.conn.ExecContext(ctx, query)
 	if err != nil {
@@ -186,7 +186,7 @@ func (o *OracleDB) ExecContext(ctx context.Context, query string) (int64, error)
 
 func (o *OracleDB) Exec(query string) (int64, error) {
 	if o.conn == nil {
-		return 0, fmt.Errorf("connection not open")
+		return 0, fmt.Errorf("连接未打开")
 	}
 	res, err := o.conn.Exec(query)
 	if err != nil {
@@ -259,7 +259,7 @@ func (o *OracleDB) GetCreateStatement(dbName, tableName string) (string, error)
 			return fmt.Sprintf("%v", val), nil
 		}
 	}
-	return "", fmt.Errorf("create statement not found")
+	return "", fmt.Errorf("未找到建表语句")
 }
 
 func (o *OracleDB) GetColumns(dbName, tableName string) ([]connection.ColumnDefinition, error) {
@@ -391,7 +391,7 @@ func (o *OracleDB) GetTriggers(dbName, tableName string) ([]connection.TriggerDe
 
 func (o *OracleDB) ApplyChanges(tableName string, changes connection.ChangeSet) error {
 	if o.conn == nil {
-		return fmt.Errorf("connection not open")
+		return fmt.Errorf("连接未打开")
 	}
 
 	tx, err := o.conn.Begin()
@@ -439,7 +439,7 @@ func (o *OracleDB) ApplyChanges(tableName string, changes connection.ChangeSet)
 		}
 		query := fmt.Sprintf("DELETE FROM %s WHERE %s", qualifiedTable, strings.Join(wheres, " AND "))
 		if _, err := tx.Exec(query, args...); err != nil {
-			return fmt.Errorf("delete error: %v", err)
+			return fmt.Errorf("删除失败：%v", err)
 		}
 	}
 
@@ -467,12 +467,12 @@ func (o *OracleDB) ApplyChanges(tableName string, changes connection.ChangeSet)
 		}
 
 		if len(wheres) == 0 {
-			return fmt.Errorf("update requires keys")
+			return fmt.Errorf("更新操作需要主键条件")
 		}
 
 		query := fmt.Sprintf("UPDATE %s SET %s WHERE %s", qualifiedTable, strings.Join(sets, ", "), strings.Join(wheres, " AND "))
 		if _, err := tx.Exec(query, args...); err != nil {
-			return fmt.Errorf("update error: %v", err)
+			return fmt.Errorf("更新失败：%v", err)
 		}
 	}
 
@@ -496,7 +496,7 @@ func (o *OracleDB) ApplyChanges(tableName string, changes connection.ChangeSet)
 
 		query := fmt.Sprintf("INSERT INTO %s (%s) VALUES (%s)", qualifiedTable, strings.Join(cols, ", "), strings.Join(placeholders, ", "))
 		if _, err := tx.Exec(query, args...); err != nil {
-			return fmt.Errorf("insert error: %v", err)
+			return fmt.Errorf("插入失败：%v", err)
 		}
 	}