Ajout diagram de gantt

src/app/milestones/milestone-detail/milestone-detail.spec.ts

@@ -31,6 +31,8 @@ const makeMilestone = (overrides: Partial<MilestoneEntity> = {}): MilestoneEntit
   id: 1,
   name: 'Sprint 1',
   description: '',
+  startDate: '',
+  endDate: '',
   dueDate: '',
   issueIds: [],
   ...overrides,
@@ -275,6 +277,46 @@ describe('MilestoneDetail', () => {
     });
   });
 
+  describe('milestoneGanttTasks', () => {
+    it('returns empty array when no linked issues', () => {
+      issuesStore.seed([]);
+      (component as any).milestone.issueIds = [];
+      expect((component as any).milestoneGanttTasks).toHaveLength(0);
+    });
+
+    it('excludes issues missing startDate or endDate', () => {
+      issuesStore.seed([
+        makeIssue({ id: 1, startDate: '2025-01-01', endDate: '' }),
+        makeIssue({ id: 2, startDate: '', endDate: '2025-01-31' }),
+      ]);
+      (component as any).milestone.issueIds = [1, 2];
+      expect((component as any).milestoneGanttTasks).toHaveLength(0);
+    });
+
+    it('returns a task for each issue with both dates', () => {
+      issuesStore.seed([
+        makeIssue({ id: 1, name: 'Task A', startDate: '2025-01-01', endDate: '2025-01-15', progress: 50 }),
+        makeIssue({ id: 2, name: 'Task B', startDate: '2025-01-10', endDate: '2025-01-31', progress: 0 }),
+      ]);
+      (component as any).milestone.issueIds = [1, 2];
+      const tasks = (component as any).milestoneGanttTasks;
+      expect(tasks).toHaveLength(2);
+      expect(tasks[0]).toMatchObject({ id: 'issue-1', name: '#1 Task A', start: '2025-01-01', end: '2025-01-15', progress: 50 });
+      expect(tasks[1]).toMatchObject({ id: 'issue-2', name: '#2 Task B', start: '2025-01-10', end: '2025-01-31', progress: 0 });
+    });
+
+    it('only includes issues linked to the milestone', () => {
+      issuesStore.seed([
+        makeIssue({ id: 1, startDate: '2025-01-01', endDate: '2025-01-31' }),
+        makeIssue({ id: 2, startDate: '2025-02-01', endDate: '2025-02-28' }),
+      ]);
+      (component as any).milestone.issueIds = [1];
+      const tasks = (component as any).milestoneGanttTasks;
+      expect(tasks).toHaveLength(1);
+      expect(tasks[0].id).toBe('issue-1');
+    });
+  });
+
   describe('issueSuggestions', () => {
     beforeEach(() => {
       issuesStore.seed([