feat: add vsm hub metadata

workplans/IHUB-WP-0019-vsm-hub-bootstrap-api.md

@@ -146,7 +146,7 @@ shell does not have `IHP_LIB`/the IHP dev environment loaded.
 
 ```task
 id: IHUB-WP-0019-T03
-status: todo
+status: done
 priority: medium
 state_hub_task_id: "a90a0220-3d02-4b97-9fbf-a6bbbfa5019c"
 ```
@@ -168,6 +168,17 @@ Candidate placement:
 Done when: `ops-hub` can be represented as the VSM Operations / System 1 hub
 without hiding that classification inside prose.
 
+Implementation note (2026-05-19): chose new nullable columns on `hubs`
+(`hub_family`, `vsm_function`, `vsm_system`) because the VSM role is hub
+identity/classification metadata, not manifest vocabulary. Added migration
+`1744588800-vsm-hub-metadata.sql`, schema constraints, v2 hub create/list/show
+JSON, hub registry JSON, compact registry/UI badges, OpenAPI request/response
+fields, SDK parameters, and validation tests. API validation now accepts either
+no VSM fields or `hubFamily=vsm` with non-empty `vsmFunction` and a supported
+`vsmSystem` (`1`, `2`, `3`, `3*`, `4`, `5`, or `environment`). `git diff
+--check` passed; `scripts/compile-check` is still blocked in this shell because
+`IHP_LIB` is not set.
+
 ---
 
 ### T04 — Add API consumer and API key bootstrap support