feat(tasks): adopt canonical task statuses

README.md

@@ -142,7 +142,7 @@ decisions (FK: topic_id, workstream_id — at least one required)
 |------|--------|
 | `topic_status` | `active` · `paused` · `archived` |
 | `workstream_status` | `proposed` · `ready` · `active` · `blocked` · `backlog` · `finished` · `archived` |
-| `task_status` | `todo` · `in_progress` · `blocked` · `done` · `cancelled` |
+| `task_status` | `wait` · `todo` · `progress` · `done` · `cancel` |
 | `task_priority` | `low` · `medium` · `high` · `critical` |
 | `decision_type` | `made` · `pending` |
 | `decision_status` | `open` · `resolved` · `escalated` · `superseded` |
@@ -150,7 +150,7 @@ decisions (FK: topic_id, workstream_id — at least one required)
 
 ### Governance constraints encoded in schema
 
-- No hard DELETE endpoints — only soft: `archived`, `cancelled`, `superseded`
+- No hard DELETE endpoints — only soft: `archived`, `cancel`, `superseded`
 - `progress_events` has no `updated_at` and no DELETE endpoint (append-only per constitution §5)
 - `decisions` with financial/legal keywords + `pending` type → auto-set `escalation_note` (§4)
 
@@ -170,12 +170,12 @@ Returns a full snapshot in one call — used by both the MCP server and dashboar
   "totals": {
     "topics":      { "active": 6, "paused": 0, "archived": 0, "total": 6 },
     "workstreams": { "ready": 1, "active": 1, "blocked": 0, "finished": 1, "total": 3 },
-    "tasks":       { "todo": 9, "in_progress": 0, "blocked": 0, "done": 11, "total": 20 },
+    "tasks":       { "wait": 0, "todo": 9, "progress": 0, "done": 11, "cancel": 0, "total": 20 },
     "decisions":   { "open": 1, "resolved": 0, "escalated": 0, "total": 1 }
   },
   "topics": [...],             // topics with nested workstream stubs
   "blocking_decisions": [...], // pending decisions only
-  "blocked_tasks": [...],
+  "waiting_tasks": [...],
   "recent_progress": [...],    // last 20 events
   "open_workstreams": [...]
 }
@@ -187,7 +187,7 @@ Returns a full snapshot in one call — used by both the MCP server and dashboar
 |--------|-----------|
 | `/topics` | CRUD (soft-delete: `archived`) |
 | `/workstreams` | CRUD (soft-delete: `archived`) |
-| `/tasks` | CRUD (soft-delete: `cancelled`); `PATCH` updates status |
+| `/tasks` | CRUD (soft-delete: `cancel`); `PATCH` updates status |
 | `/decisions` | CRUD (soft-delete: `superseded`); auto-escalation |
 | `/progress` | `GET` list + `POST` append — no DELETE |
 | `/state/summary` | Full snapshot |