Fixes: FRMW-2965
In this PR we replace/remove the existing step to normalize a CSV file with the newly written CSV normalizer and also we validate the file contents further using a Zod schema.
I have duplicated the schema for now. But it is makes sense to re-use the schema for CSV validating and `/admin/products/batch`, then I can keep one source of truth under utils and re-export it. WDYT?
**Screenshots of some errors after validating the file strictly**

