fix: implement formula field, list field, and reference field as chilrden of the field class. fix: when converting api response data to appropriate field response make sure json field objects are converted to correct field class based upon type.

src/models/ListValue.ts

@@ -0,0 +1,21 @@
+export class ListValue {
+  public id: string;
+  public name: string;
+  public sortOrder: number;
+  public numericValue: number;
+  public color: string;
+
+  constructor(
+    id: string,
+    name: string,
+    sortOrder: number,
+    numericValue: number,
+    color: string
+  ) {
+    this.id = id;
+    this.name = name;
+    this.sortOrder = sortOrder;
+    this.numericValue = numericValue;
+    this.color = color;
+  }
+}