feat(evaluations): enrich eval tests with attack path, criteria and data sources

- Capture Step.Description (HTML stripped), step name/number, substep ref,
  criteria, and data sources from MITRE ATT&CK Evaluations API
- _aggregate_by_technique() now accumulates ALL occurrences per technique
  (multiple substep refs, criteria, step contexts) instead of keeping only
  the best-scoring one
- New helper functions _build_procedure_text(), _build_description(),
  _build_red_summary() generate rich narratives from accumulated occurrences
- New re_enrich_evaluation_round() service function + POST endpoint
  /system/attck-evaluations/re-enrich to update already-imported tests
  without changing detection results or validation state
- Frontend: Re-enrich button per imported round + result banner in SystemPage

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/app/routers/system.py

@@ -747,6 +747,41 @@ def get_pending_evaluation_count(
     return {"pending": count}
 
 
+@router.post("/attck-evaluations/re-enrich")
+def re_enrich_evaluation_round(
+    payload: dict,
+    db: Session = Depends(get_db),
+    current_user: User = Depends(require_role("admin")),
+):
+    """Re-enrich already-imported evaluation tests with rich data from the MITRE API.
+
+    Updates procedure_text (attack path + criteria), description (data sources +
+    substep references) and red_summary — without changing detection results,
+    state or validation status.
+
+    Body: { "adversary_name": "turla", "adversary_display": "Turla", "eval_round": 5 }
+
+    Useful to upgrade tests that were imported before the enrichment feature
+    was added.
+    """
+    from app.services.attck_evaluations_service import re_enrich_evaluation_round as _re_enrich
+
+    adversary_name = payload.get("adversary_name", "")
+    adversary_display = payload.get("adversary_display", adversary_name)
+    eval_round = payload.get("eval_round", 0)
+
+    if not adversary_name or not eval_round:
+        raise HTTPException(status_code=400, detail="adversary_name and eval_round are required")
+
+    try:
+        summary = _re_enrich(db, adversary_name, adversary_display, eval_round, current_user)
+    except Exception as exc:
+        logger.error("ATT&CK Evaluation re-enrich failed: %s", exc, exc_info=True)
+        raise HTTPException(status_code=502, detail=f"Re-enrich failed: {exc}")
+
+    return summary
+
+
 @router.post("/email-test")
 def send_test_email(
     payload: EmailTestRequest,