Resolve Customer Account question; add commercial subscription research

Record B2B SaaS subscriber tenancy and Stripe billing source notes. Resolve
the Customer Account open question: reject it as canonical, add Commercial
Record and Commercial Relationship to the Record and relationship layers, and
document Subscriber as a convenience term only.

canon/CanonicalGlossary.md

@@ -146,15 +146,39 @@ An organization or other actor recognized by a legal system.
 
 ## Customer
 
-An actor in a commercial or service-consumption relationship.
+A commercial role played by an actor (usually an Organization, sometimes a
+Natural Person for individual subscriptions) that consumes services from a
+vendor.
 
-Customer is a relationship role, not automatically a tenant or organization.
+Customer is a relationship role, not a record type and not interchangeable with
+Tenant, Organization, Account, or Commercial Record.
 
 ## Vendor
 
-An actor in a service-provider relationship.
+A commercial role played by an actor (usually an Organization) that provides
+services to customer actors.
 
-Vendor is a relationship role, not automatically a tenant or organization.
+Vendor is a relationship role, not a tenant, realm, or organization synonym.
+
+## Commercial Relationship
+
+A typed relationship connecting a vendor actor to a customer actor for a
+commercial or subscription purpose within a stated scope.
+
+May reference a Commercial Record for billing state. Does not imply membership,
+authorization, or identity equivalence.
+
+## Commercial Record
+
+A record in a billing, CRM, or commerce system that tracks payment methods,
+subscriptions, invoices, contracts, or commercial contact details for an actor
+or tenant.
+
+Examples: Stripe Customer, Salesforce Account, subscription billing profile.
+
+Commercial Record is in the Record layer. It is not an Account (login), not an
+Organization actor, and not a Customer Account. Link it to Actor, Tenant, or
+Scope via Identifier binding or Commercial Relationship.
 
 ## Community
 
@@ -292,3 +316,19 @@ pseudonymization with separately stored re-identification keys.
 `User` may be used in prose when quoting or mapping external systems, but it
 should not be a canonical root concept. Resolve it to a specific canonical
 concept before using it in model definitions.
+
+## Non-Canonical Convenience Term: Subscriber
+
+`Subscriber` (common in Auth0 B2B SaaS documentation) usually means the
+organization or party holding a subscription and tenant. Resolve to Organization
++ Customer Relationship role + Tenant Scope, or to Natural Person + Tenant for
+individual subscriptions. Do not model as Customer Account or Account.
+
+## Non-Canonical Convenience Term: Customer Account
+
+Do not use `Customer Account` as a canonical term. Resolve by layer:
+
+- login/access → Account;
+- subscribing company → Organization + Customer Relationship role;
+- billing/CRM record → Commercial Record;
+- isolation boundary → Tenant.