feat: definition of done per project

A project can ask that tickets reach a DONE status only with their
checklist ticked (settings.checklistBeforeDone, off by default; absent
when saving means unchanged). Members get a 422 telling how many steps are
left; owners and admins may still close it. Settings has the switch and
the ticket's checklist says when the project asks for it.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

libs/api/tracker/presenters/src/lib/graphql/inputs.ts

@@ -772,6 +772,15 @@ export class ProjectSettingsInput {
   @ValidateNested({ each: true })
   @Type(() => CustomFieldDefinitionInput)
   customFields?: CustomFieldDefinitionInput[];
+
+  @Field({
+    nullable: true,
+    description:
+      'Definition of done: DONE only with the checklist ticked. Absent: unchanged',
+  })
+  @IsOptional()
+  @IsBoolean()
+  checklistBeforeDone?: boolean;
 }
 
 @InputType({

libs/api/tracker/presenters/src/lib/graphql/types.ts

@@ -115,6 +115,11 @@ export class ProjectSettingsGql {
   @Field(() => [AreaOptionGql]) areas!: AreaOptionGql[];
   @Field(() => [CustomFieldDefinitionGql])
   customFields!: CustomFieldDefinitionGql[];
+  @Field({
+    description:
+      'Definition of done: tickets reach DONE only with their checklist ticked (owners and admins may override)',
+  })
+  checklistBeforeDone!: boolean;
 }
 
 @ObjectType('Project')