docs: complete hub-core package slice

docs/hub-core-extraction-boundary.md

@@ -74,6 +74,9 @@ Current implementation status:
 - 2026-06-06: progress event and capability request adapter seams were added.
   Hub-core uses generic JSON context fields where State Hub currently has
   dev-specific workstream/task/topic/decision foreign keys.
+- 2026-06-07: progress and capability REST router factories were added. T05 now
+  has the package-side models, schemas, routers, migration scaffold, and shared
+  utilities needed before T06/T08.
 
 ## Extract Now
 
@@ -92,6 +95,8 @@ rewriting and small router seams:
 | `api/schemas/agent_message.py` | Generic message schemas. |
 | `api/schemas/tpsc.py` | Generic TPSC schemas. |
 | `api/routers/messages.py` | Mostly self-contained generic router. |
+| `api/routers/progress.py` | Generic progress-event router once dev-hub foreign keys move behind `subject_refs` or extension mapping. |
+| `api/routers/capability_requests.py` | Generic capability catalog/request router once dev-hub flow side effects and task unblocking stay in dev-hub. |
 | `api/routers/tpsc.py` | Generic catalog and GDPR report router. |
 | `api/routers/policy.py` | Generic policy document router if policy roots become configurable. |