curl -X GET "https://api.chanl.ai/api/v1/workspaces/ws_123/personas/stats" \
  -H "Authorization: Bearer <access_token>"

{
  "success": true,
  "data": {
    "stats": {
      "overview": {
        "total_personas": 15,
        "active_personas": 12,
        "total_simulations": 1456,
        "avg_score_all_personas": 83.7
      },
      "most_used_persona": {
        "id": "persona_123",
        "name": "Frustrated Customer",
        "usage_count": 234,
        "avg_score": 72.3,
        "success_rate": 89.2
      },
      "best_performing_persona": {
        "id": "persona_456",
        "name": "Polite Customer",
        "usage_count": 189,
        "avg_score": 94.1,
        "success_rate": 98.4
      },
      "worst_performing_persona": {
        "id": "persona_789",
        "name": "Very Difficult Customer",
        "usage_count": 67,
        "avg_score": 58.3,
        "success_rate": 73.1
      },
      "personas_by_emotion": {
        "frustrated": {
          "count": 3,
          "avg_score": 71.2,
          "total_simulations": 345
        },
        "happy": {
          "count": 2,
          "avg_score": 92.7,
          "total_simulations": 234
        },
        "confused": {
          "count": 4,
          "avg_score": 78.9,
          "total_simulations": 289
        },
        "neutral": {
          "count": 6,
          "avg_score": 86.4,
          "total_simulations": 588
        }
      },
      "personas_by_difficulty": {
        "easy": {
          "count": 5,
          "avg_score": 91.3,
          "total_simulations": 456
        },
        "medium": {
          "count": 7,
          "avg_score": 81.7,
          "total_simulations": 623
        },
        "hard": {
          "count": 3,
          "avg_score": 69.2,
          "total_simulations": 377
        }
      },
      "personas_by_language": {
        "en": {
          "count": 12,
          "avg_score": 84.1
        },
        "es": {
          "count": 2,
          "avg_score": 81.3
        },
        "fr": {
          "count": 1,
          "avg_score": 79.8
        }
      },
      "usage_trends": {
        "last_7_days": {
          "total_simulations": 89,
          "avg_score": 85.2,
          "most_used": "persona_123"
        },
        "last_30_days": {
          "total_simulations": 378,
          "avg_score": 83.9,
          "most_used": "persona_123"
        }
      },
      "performance_insights": [
        {
          "type": "recommendation",
          "message": "Consider creating more 'easy' difficulty personas - they show highest success rates"
        },
        {
          "type": "warning",
          "message": "Persona 'Very Difficult Customer' has low scores - review and optimize"
        },
        {
          "type": "insight",
          "message": "Frustrated personas are used frequently but have lower scores - good for stress testing"
        }
      ]
    }
  }
}