feat: update task statistics calculation

- Renamed variables in `getTaskStats` for clarity, changing `completed` to `done` and ensuring `archived` is counted separately.
- Added logic to calculate `completed` tasks as the sum of `done` and `archived`, improving task status reporting.

src/services/task-management/tasks.ts

@@ -254,17 +254,19 @@ export class TasksService {
    * Récupère les statistiques des tâches
    */
   async getTaskStats() {
-    const [total, completed, inProgress, todo, backlog, cancelled, freeze, archived] = await Promise.all([
+    const [total, done, archived, inProgress, todo, backlog, cancelled, freeze] = await Promise.all([
       prisma.task.count(),
       prisma.task.count({ where: { status: 'done' } }),
+      prisma.task.count({ where: { status: 'archived' } }),
       prisma.task.count({ where: { status: 'in_progress' } }),
       prisma.task.count({ where: { status: 'todo' } }),
       prisma.task.count({ where: { status: 'backlog' } }),
       prisma.task.count({ where: { status: 'cancelled' } }),
-      prisma.task.count({ where: { status: 'freeze' } }),
-      prisma.task.count({ where: { status: 'archived' } })
+      prisma.task.count({ where: { status: 'freeze' } })
     ]);
 
+    const completed = done + archived; // Terminées = Done + Archived
+
     return {
       total,
       completed,