External systems and vendor APIs

Vendor catalog — one table: who the vendor is, what the API is for, link to official docs. Updated manually.

API landscape — same integrations, grouped by theme (quick view).

Google Workspace APIs — Gmail, Calendar, and Drive.

Integration building blocks — ConnectSoft libraries (OAuth, SMS providers, typed HTTP clients, SaaS multitenancy pointers).

SaaS multitenancy (not a vendor product) lives in SaaS extensions — package handbooks and integration.