fix: Change default .arrow compression to "uncompressed"

[dangotbanned]

Fixes #655

The file size of flights-200k.arrow has a 7.2x 2.4x increase.
However, this is still roughly half 0.16x the size of flights-200k.json.

Also, adds support for overriding any write_options on a per-Spec basis.
This may be helpful if we later run into issues with vega/vega#3961

[dangotbanned]

@jheer

I'm not sure how to reproduce this check on the buffer you have in flechette:
https://github.com/uwdata/flechette/blob/0b1b7a1a2facc89746cf541fca37b06878c316f3/src/decode/record-batch.js#L11-L20

I think this PR should resolve the issue.
However, I'd feel more confident merging if you were able to verify the new version can be decoded on your end 👍

• https://github.com/vega/vega-datasets/raw/refs/heads/remove-arrow-compression/data/flights-200k.arrow

[jheer]

@jheer

I'm not sure how to reproduce this check on the buffer you have in flechette: https://github.com/uwdata/flechette/blob/0b1b7a1a2facc89746cf541fca37b06878c316f3/src/decode/record-batch.js#L11-L20

I think this PR should resolve the issue. However, I'd feel more confident merging if you were able to verify the new version can be decoded on your end 👍

* https://github.com/vega/vega-datasets/raw/refs/heads/remove-arrow-compression/data/flights-200k.arrow

I can confirm that the file parses successfully with both Arrow-JS and Flechette. However, the internal format has changed, which may affect downstream use:

• The column data types have changed. In particular, 64-bit integers are now being used for the delay and distance fields. Previously I believe 16-bit integers were used. This change (1) bloats the file size significantly and (2) might break or complicate downstream use for some users as Arrow-JS will now return BigInt values rather than number values for those columns.
• (Minor) The previous version consisted of multiple record batches. It appears the new version consists of a single record batch. If any tools were leveraging that (e.g., to test multi-batch decoding), that no longer holds. However, I don't think this is much of an issue.

I would think that the simplest fix would be to revert to how the file was originally constructed. Why make changes if they are not needed?

[dangotbanned]

#656 (comment)

Thanks for testing it out @jheer

I'm going to take a deeper look at the previous version to try and more faithfully recreate it.

I think the datatypes should be easy to fix