Phase 28-36 body of work

Accumulated since a6f12e2 (Phase 21 Rust port + Phase 27 versioning):

- Phase 36: embed_semaphore on VectorState (permits=1) serializes
  seed embed calls — prevents sidecar socket collisions under
  concurrent /seed stress load
- Phase 31+: run_stress.ts 6-task diverse stress scaffolding;
  run_e2e_rated.ts + orchestrator.ts tightening
- Catalog dedupe cleanup: 16 duplicate manifests removed; canonical
  candidates.parquet (10.5MB -> 76KB) + placements.parquet (1.2MB ->
  11KB) regenerated post-dedupe; fresh manifests for active datasets
- vectord: harness EvalSet refinements (+181), agent portfolio
  rotation + ingest triggers (+158), autotune + rag adjustments
- catalogd/storaged/ingestd/mcp-server: misc tightening
- docs: Phase 28-36 PRD entries + DECISIONS ADR additions;
  control-plane pivot banner added to top of docs/PRD.md (pointing
  at docs/CONTROL_PLANE_PRD.md which lands in next commit)

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

data/_catalog/manifests/32ee74a0-59b4-4e5b-8edb-70c9347a4bf3.json

@@ -0,0 +1,26 @@
+{
+  "id": "32ee74a0-59b4-4e5b-8edb-70c9347a4bf3",
+  "name": "successful_playbooks_live",
+  "schema_fingerprint": "4e28e94650d9f5689e952674aebfd09db70edfcba617713081c0a83bf59121ce",
+  "objects": [
+    {
+      "bucket": "primary",
+      "key": "datasets/successful_playbooks_live.parquet",
+      "size_bytes": 284341,
+      "created_at": "2026-04-22T03:28:28.343840136Z"
+    }
+  ],
+  "created_at": "2026-04-20T11:07:57.308050648Z",
+  "updated_at": "2026-04-22T03:28:28.343843823Z",
+  "description": "",
+  "owner": "",
+  "sensitivity": null,
+  "columns": [],
+  "lineage": null,
+  "freshness": null,
+  "tags": [],
+  "row_count": null,
+  "last_embedded_at": null,
+  "embedding_stale_since": null,
+  "embedding_refresh_policy": null
+}