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/domain/src/lib/project/project-settings.spec.ts

@@ -353,4 +353,54 @@ describe('Project settings', () => {
       });
     });
   });
+
+  it('holds a ticket with an unticked checklist out of DONE, if asked', () => {
+    const project = newProject();
+    const issue = new IssueFactory().create(
+      {
+        projectId: project.id,
+        projectKey: 'WEB',
+        number: 1,
+        title: 'Pago',
+        type: 'TASK',
+        reporterId: 'dev',
+      },
+      project.workflow,
+    );
+    issue.addChecklistItem('dev', 'a', 'Probar en Safari');
+    issue.addChecklistItem('dev', 'b', 'Probar en Chrome');
+    for (const to of [
+      'TODO',
+      'IN_PROGRESS',
+      'IN_REVIEW',
+      'READY_FOR_QA',
+      'IN_QA',
+    ])
+      issue.changeStatus('dev', to, null, project.workflow);
+
+    // Off by default: nothing changes for projects that do not ask.
+    const done = () =>
+      issue.changeStatus('dev', 'DONE', null, project.workflow);
+    expect(project.workflow.checklistBeforeDone).toBe(false);
+
+    project.updateSettings('owner', {
+      ...defaultProjectSettings(),
+      checklistBeforeDone: true,
+    });
+    expect(done).toThrow(/quedan 2 pasos/);
+    // A client that does not know about it keeps it on.
+    project.updateSettings('owner', defaultProjectSettings());
+    expect(project.workflow.checklistBeforeDone).toBe(true);
+    issue.updateChecklistItem('dev', 'a', { done: true });
+    expect(done).toThrow(/queda 1 paso/);
+    // An owner or admin may close it anyway.
+    issue.changeStatus('owner', 'DONE', null, project.workflow, true);
+    expect(issue.status).toBe('DONE');
+
+    project.updateSettings('owner', {
+      ...defaultProjectSettings(),
+      checklistBeforeDone: false,
+    });
+    expect(project.workflow.checklistBeforeDone).toBe(false);
+  });
 });