feat(classification-spine): implement STATE-WP-0065 repo-anchored model

Replace the ad-hoc coordination-domain spine with the Repo Classification
Standard: 14 market domains, classification columns on managed_repos, and
workplans anchored by repo_id (topic_id optional).

- Add Alembic migration d8e9f0a1b2c3 with data backfill and workstream→workplan rename
- Add api/classification.py validation and register-from-classification tooling
- Expose workplan-first REST/MCP surface with legacy workstream aliases
- Add C-24 consistency rule and legacy domain frontmatter mapping
- Update dashboard repos page with category/capability/stake filters
- Update orientation docs; mark STATE-WP-0065 finished

.claude/rules/architecture.md

@@ -1,8 +1,15 @@
 ## Architecture
 
-<!-- TODO: Describe the key design decisions and component structure.
-     Key modules, data flows, external integrations, state machines, etc. -->
+State Hub uses a **repo-anchored classification spine** (STATE-WP-0065):
+
+- **Primary anchor:** `managed_repos` + committed `.repo-classification.yaml`
+- **Market domain:** derived from classification (`domain` field) — 14 fixed values
+- **Workplans:** table `workplans`, `repo_id` required, `topic_id` optional
+- **Legacy:** `/workstreams/` REST routes and `workstream_*` MCP tools are aliases
+
+Classification canon lives in `the-custodian/canon/standards/`.
+Validation: `api/classification.py` · registration: `make register-from-classification`.
 
 ## Quick Reference
 
-`~/state-hub/mcp_server/TOOLS.md` — MCP tool reference
+`~/state-hub/mcp_server/TOOLS.md` — MCP tool reference