data: add Fallax for Startups

[J36-Ai-Editer]

Summary

• add the missing Fallax vendor record
• model one active startup offer with 50 free seats for 12 months
• capture the full-product access, compliance-evidence export, and published eligibility rules from first-party Fallax sources

Validation

• pinned Sourcey Catalog Verifier: valid (1 vendor, 1 program, 1 offer)
• git diff --check
• DCO signed-off commit

Closes #762