Change CreateEngagement inputs to create their prop lists from native esm classes

This works as long as there is no type mapping in the inheritance chain.
This is fine for this single use case.
And this can also go away once we finish Gel migration.

Author: CarsonF

src/components/engagement/dto/create-engagement.dto.ts

@@ -1,9 +1,9 @@
 import { Field, InputType, ObjectType } from '@nestjs/graphql';
+import { entries } from '@seedcompany/common';
 import { Type } from 'class-transformer';
 import { ValidateNested } from 'class-validator';
 import { stripIndent } from 'common-tags';
-import { keys as keysOf } from 'ts-transformer-keys';
-import { CalendarDate, DateField, ID, IdField } from '~/common';
+import { CalendarDate, DataObject, DateField, ID, IdField } from '~/common';
 import { ChangesetIdField } from '../../changeset';
 import { CreateDefinedFileVersionInput } from '../../file/dto';
 import { LanguageMilestone } from '../../language/dto';
@@ -16,7 +16,7 @@ import { EngagementStatus } from './status.enum';
 @InputType({
   isAbstract: true,
 })
-export abstract class CreateEngagement {
+export abstract class CreateEngagement extends DataObject {
   @IdField()
   readonly projectId: ID;
 
@@ -37,8 +37,11 @@ export abstract class CreateEngagement {
 }
 
 @InputType()
-export abstract class CreateLanguageEngagement extends CreateEngagement {
-  static readonly Props = keysOf<CreateLanguageEngagement>();
+export class CreateLanguageEngagement extends CreateEngagement {
+  // Warning: this only works if not doing inheritance type mapping
+  static readonly Props = entries(
+    CreateLanguageEngagement.defaultValue(CreateLanguageEngagement),
+  ).map(([k]) => k);
 
   @IdField()
   readonly languageId: ID;
@@ -81,8 +84,11 @@ export abstract class CreateLanguageEngagement extends CreateEngagement {
 }
 
 @InputType()
-export abstract class CreateInternshipEngagement extends CreateEngagement {
-  static readonly Props = keysOf<CreateInternshipEngagement>();
+export class CreateInternshipEngagement extends CreateEngagement {
+  // Warning: this only works if not doing inheritance type mapping
+  static readonly Props = entries(
+    CreateInternshipEngagement.defaultValue(CreateInternshipEngagement),
+  ).map(([k]) => k);
 
   @IdField()
   readonly internId: ID;