…select into outfile` (apache#25854)

This pr do two things:
1. Infer the column name if the column is expression in `select into outfile`. The rule for column name generation can be refered in pr: apache#24990 
2. fix bug that it will core dump if the `_schema` fails to build in the open phase in vorc_transformer.cpp


TODO:
1. Support infer the column name if the column is expression in `select into outfile` in new optimizer(Nereids).

…25946)

This pr makes three changes to the display of complex types：
1. NULL value in complex types refers to being displayed as `null`, not `NULL`
2. struct type is displayed as "column_name": column_value
3. Time types such as `datetime` and `date`, are displayed with double quotes in complex types. like
    `{1, "2023-10-26 12:12:12"}`

This pr also do a code refactor:
1. nesting_level is set to a member variable of the `DataTypeSerDe`, rather than a parameter in methods.

What's more, this pr fix a bug that fileSize is not correct, introduced by this pr: #25854

…pache#25946)

This pr makes three changes to the display of complex types：
1. NULL value in complex types refers to being displayed as `null`, not `NULL`
2. struct type is displayed as "column_name": column_value
3. Time types such as `datetime` and `date`, are displayed with double quotes in complex types. like
    `{1, "2023-10-26 12:12:12"}`

This pr also do a code refactor:
1. nesting_level is set to a member variable of the `DataTypeSerDe`, rather than a parameter in methods.

What's more, this pr fix a bug that fileSize is not correct, introduced by this pr: apache#25854

…pache#25946)

This pr makes three changes to the display of complex types：
1. NULL value in complex types refers to being displayed as `null`, not `NULL`
2. struct type is displayed as "column_name": column_value
3. Time types such as `datetime` and `date`, are displayed with double quotes in complex types. like
    `{1, "2023-10-26 12:12:12"}`

This pr also do a code refactor:
1. nesting_level is set to a member variable of the `DataTypeSerDe`, rather than a parameter in methods.

What's more, this pr fix a bug that fileSize is not correct, introduced by this pr: apache#25854

…pache#25946)

This pr makes three changes to the display of complex types：
1. NULL value in complex types refers to being displayed as `null`, not `NULL`
2. struct type is displayed as "column_name": column_value
3. Time types such as `datetime` and `date`, are displayed with double quotes in complex types. like
    `{1, "2023-10-26 12:12:12"}`

This pr also do a code refactor:
1. nesting_level is set to a member variable of the `DataTypeSerDe`, rather than a parameter in methods.

What's more, this pr fix a bug that fileSize is not correct, introduced by this pr: apache#25854

…pache#25946)

This pr makes three changes to the display of complex types：
1. NULL value in complex types refers to being displayed as `null`, not `NULL`
2. struct type is displayed as "column_name": column_value
3. Time types such as `datetime` and `date`, are displayed with double quotes in complex types. like
    `{1, "2023-10-26 12:12:12"}`

This pr also do a code refactor:
1. nesting_level is set to a member variable of the `DataTypeSerDe`, rather than a parameter in methods.

What's more, this pr fix a bug that fileSize is not correct, introduced by this pr: apache#25854

…pache#25946)

This pr makes three changes to the display of complex types：
1. NULL value in complex types refers to being displayed as `null`, not `NULL`
2. struct type is displayed as "column_name": column_value
3. Time types such as `datetime` and `date`, are displayed with double quotes in complex types. like
    `{1, "2023-10-26 12:12:12"}`

This pr also do a code refactor:
1. nesting_level is set to a member variable of the `DataTypeSerDe`, rather than a parameter in methods.

What's more, this pr fix a bug that fileSize is not correct, introduced by this pr: apache#25854

…select into outfile` (apache#25854)

This pr do two things:
1. Infer the column name if the column is expression in `select into outfile`. The rule for column name generation can be refered in pr: apache#24990 
2. fix bug that it will core dump if the `_schema` fails to build in the open phase in vorc_transformer.cpp


TODO:
1. Support infer the column name if the column is expression in `select into outfile` in new optimizer(Nereids).

…pache#25946)

This pr makes three changes to the display of complex types：
1. NULL value in complex types refers to being displayed as `null`, not `NULL`
2. struct type is displayed as "column_name": column_value
3. Time types such as `datetime` and `date`, are displayed with double quotes in complex types. like
    `{1, "2023-10-26 12:12:12"}`

This pr also do a code refactor:
1. nesting_level is set to a member variable of the `DataTypeSerDe`, rather than a parameter in methods.

What's more, this pr fix a bug that fileSize is not correct, introduced by this pr: apache#25854