Slack/Gmail/Calendar/HubSpot each grew a bespoke accounts module; this
is the same proven shape parameterized by connector: profiles at
<name>:account:<id>, pointer-only :default, lazy legacy migration. A
descriptor opts in via account_field (creds field or @identity). Connect
adds accounts instead of overwriting, connector_list grows a generic
accounts branch, and /v1/connectors/{name}/accounts/{id}/disconnect|default
routes cover every account-patterned connector. Spec for the batch in
docs/CONNECTORS-BATCH2-SPEC.md.
Rohit C Prasad