fix some derived data that was removed elsewhere

src/components/EntitySummaryButton.vue

@@ -74,10 +74,6 @@ export default class EntitySummaryButton extends Vue {
   @Prop({ required: true })
   entity!: EntityData | Contact | null;
 
-  /** Type of entity: 'person' or 'project' */
-  @Prop({ required: true })
-  entityType!: "person" | "project";
-
   /** Display label for the entity role */
   @Prop({ required: true })
   label!: string;
@@ -92,6 +88,10 @@ export default class EntitySummaryButton extends Vue {
     entity: EntityData | Contact | null;
   }) => void | Promise<void>;
 
+  get entityType(): string {
+    return this.entity && "handleId" in this.entity ? "project" : "person";
+  }
+
   /**
    * CSS classes for the main container
    */