test: Federation flow for company entities

Context

We have implemented auto_federate for contacts. Now we need to extend and test federation for company entities.

Current State

• process_contact_identifiers extracts emails/phones from contacts' JSONB fields
• Companies don't have the same JSONB structure for identifiers
• Companies may share identifiers through:
• URLs (website)
• Contact emails (employees)
• Phone numbers

Tasks

• [ ] Determine what identifiers companies should be federated on
• [ ] Create process_company_identifiers function (if needed)
• [ ] Add test: Two companies with same website URL get federated
• [ ] Add test: Two companies with same contact email get federated
• [ ] Verify company federation respects federated_id.entity_type = 'company'

Questions

• Should company federation be based on URLs primarily?
• Should company contacts (employees) contribute to company federation?

Related

• ADR-017: Unified Identifiers
• auto_federate action in federation-manage edge function