Fix `Arrow datatype Extension(...) not supported by Polars` error
Some datasets use extension arrow datatypes ([`ArrayXD`](https://github.com/huggingface/datasets/blob/2.18.0/src/datasets/features/features.py#L524)) which are not supported by polars. Using `pl.read_parquet()` or `pl.scan_parquet()` throws an error:
```
"Arrow datatype {dt:?} not supported by Polars. You probably need to activate that data-type feature."
```
even when passing only columns of supported datatypes with `column=[name]` argument.

This PR uses pyarrow to read data directly instead of reading with polars and then pass supported columns to polars.
This PR just ignores such extension columns since it doesn't make much sense to compute anything basic over fixed size arrays, and also this feature is rarely used. This can be extended in a future PR to return for example arrays shape.

will fix https://github.com/huggingface/dataset-viewer/issues/2679
Fix `Arrow datatype Extension(...) not supported by Polars` error: Some datasets use extension arrow datatypes ([`ArrayXD`](https://github.com/huggingface/datasets/blob/2.18.0/src/datasets/features/features.py#L524)) which are not supported by polars. Using `pl.read_parquet()` or `pl.scan_parquet()` throws an error:
```
"Arrow datatype {dt:?} not supported by Polars. You probably need to activate that data-type feature."
```
even when passing only columns of supported datatypes with `column=[name]` argument.

This PR uses pyarrow to read data directly instead of reading with polars and then pass supported columns to polars.
This PR just ignores such extension columns since it doesn't make much sense to compute anything basic over fixed size arrays, and also this feature is rarely used. This can be extended in a future PR to return for example arrays shape.

will fix https://github.com/huggingface/dataset-viewer/issues/2679