feat(validation): support multiple delimiters, and return multiple validation errors, and return headers

This PR includes some additional validations to return a list of columns that failed to be parsed, as currently it returns the column that failed to be parsed. In addition, I have added a feature to return the headers of the csv, and also another validation that if any row has more columns than the indices, it returns an error - for instance having 4 columns, but rows contain more than 4 columns.

The idea is to return a list of validations to the user so that the majority of the errors can be fixed without re-validating the csv again - for instance avoiding uploading the csv to the server and validating which would save bandwidth and time

Thanks for your PR. I am currently in China and it’s hard for me to review it appropriately. Could you describe the changes and why they were necessary? That would be great, thanks!

Updated description