Promote CSV Schema Inference Logic to arrow-cast

**Is your feature request related to a problem or challenge? Please describe what you are trying to do.**

The CSV reader currently contains private logic for inferring `DataType` from strings. Splitting it out not only allows using it elsewhere, such as in arrow-json, but also will help preserving consistency with the parsing logic #4131

**Describe the solution you'd like**

Extract the CSV inference logic into arrow-cast

**Describe alternatives you've considered**

**Additional context**