Vendor-aware mapping

Every partner has an implementation guide on top of the base X12 spec. Kairos ships vendor overlays that encode envelope IDs, required fields, and fixed values so you don't have to re-read a PDF for every partner.

How to use it

1. Open a mapping or the upload page
2. Click the vendor selector, search by name
3. Kairos applies envelope defaults (ISA qualifiers, GS08 version, GS01 code)
4. Vendor-required rows are highlighted; missing ones fail activation
5. Vendor-specific fixed values are pinned on writeback

Adding a vendor

Edit src/lib/vendors/catalog.ts and src/lib/vendors/requirements.ts to add a new vendor, its supported transactions, and per-transaction overlay. Docs pages under /docs/vendors are generated from the same source.