limit to scalar result type from custom query

Pushing further limits to customer that is engineering the query anyhow.
Result type of any query must be reduced to a scalar.

Looks to be best approach for now as enforcing any start or endtime
deltas seems too confining for consumers.

Also parsing arbitratry query results appears intractable currently
and lacks any justifiable accuracy.

breeder/linux_network_stack/effectuation.py

@@ -60,8 +60,20 @@ def run_reconnaissance():
                     query_name = objective.get('name')
 
                     query_result = prom_conn.custom_query(recon_query)
-                    metric_value = query_result[0]
-                    metric_data[query_name] = metric_value.get('value')[1]
+
+                    if query_result.get('resultType') != 'scalar':
+                        raise Exception("Custom Query must be of result type scalar.")
+
+                    # Example format of result processed
+                    #   "data": {
+                    #       "resultType": "scalar",
+                    #       "result": [
+                    #         1703619892.31, << TS
+                    #         "0.401370548"  << Value
+                    #       ]
+                    #     }
+
+                    metric_data[query_name] = metric_value.get('result')[1]
                 else:
                     raise Exception("Reconnaisance service type {recon_service_type} not supported yet.")