TMSS-528: use station_groups for specifying beamforming stations.

SAS/TMSS/backend/src/tmss/tmssapp/schemas/task_template-beamforming_observation-1.json

@@ -258,10 +258,15 @@
               "enabled"
             ]
           },
-          "stations": {
-            "description": "When observing beamforming is done on the intersection of all stations in this list and the used stations in the observation. So, specifyng all possible stations here means that all observation-stations are used. Specifying a small subset here means that only the observing-stations in this small list are used.",
-            "$ref": "http://tmss.lofar.org/api/schemas/commonschematemplate/stations/1/#/definitions/station_list",
-            "default": ["CS001", "CS002", "CS003", "CS004", "CS005", "CS006", "CS007", "CS011", "CS013", "CS017", "CS021", "CS024", "CS026", "CS028", "CS030", "CS031", "CS032", "CS301", "CS302", "CS401", "CS501", "RS106", "RS205", "RS208", "RS210", "RS305", "RS306", "RS307", "RS310", "RS406", "RS407", "RS409", "RS503", "RS508", "RS509", "DE601", "DE602", "DE603", "DE604", "DE605", "DE609", "FR606", "SE607", "UK608", "PL610", "PL611", "PL612", "IE613", "LV614"],
+          "station_groups": {
+            "description": "While observing, COBALT will beamform on the intersection of all stations in this list and the used stations in the observation. So, specifying all possible stations here means that all observation-stations are used. Specifying a small subset here means that only the observing-stations in this small list are used. By default we let COBALT beamform on the Core stations.",
+            "$ref": "http://tmss.lofar.org/api/schemas/commonschematemplate/stations/1#/definitions/station_groups",
+            "default": [
+              {
+                "stations": ["CS001", "CS002", "CS003", "CS004", "CS005", "CS006", "CS007", "CS011", "CS013", "CS017", "CS021", "CS024", "CS026", "CS028", "CS030", "CS031", "CS032", "CS301", "CS302", "CS401", "CS501"],
+                "max_nr_missing": 1
+              }
+            ],
             "minItems": 1
           }
         },
@@ -270,7 +275,7 @@
           "coherent",
           "incoherent",
           "flys eye",
-          "stations"
+          "station_groups"
         ]
       }
     }