fix: building csv if the amount of langugage varys between participants

Author: stampaaaron

apps/backend/src/system/reports/reports.service.ts

@@ -24,6 +24,8 @@ export class ReportsService {
       ],
     });
 
+    const columnKeys = new Set(['participant'])
+
     const evaluatedExposurePerParticipant = participants.map((participant) => {
       const exposure = this.getParticipantExposure(participant);
       const sortedExposureEntries = Array.from(exposure).sort(([_a, exposureA], [_b, exposureB]) => exposureB - exposureA);
@@ -34,14 +36,15 @@ export class ReportsService {
           acc[`L${index + 1}`] = duration / exposureSum;
           acc[`L${index + 1}_id`] = language.id;
           acc[`L${index + 1}_name`] = language.name;
+          columnKeys.add(`L${index + 1}`).add(`L${index + 1}_id`).add(`L${index + 1}_name`)
 
           return acc;
         },
         { participant: participant.id }
       );
     });
 
-    return stringify(evaluatedExposurePerParticipant, { header: true });
+    return stringify(evaluatedExposurePerParticipant, { header: true, columns: Array.from(columnKeys) });
   }
 
   getParticipantExposure(participant: Participant) {