feat: add filter for completed tasks in the last 7 days

- Implemented `showCompletedLast7Days` filter in `KanbanFilters` to toggle visibility of tasks completed in the last week.
- Updated `GeneralFilters` to include a new filter chip for the completed tasks toggle.
- Enhanced `TasksProvider` to filter tasks based on the new criteria, improving task management capabilities.
- Adjusted `FilterSummary` to display the active filter status for better user feedback.

src/components/ui/TaskCard.tsx

@@ -517,10 +517,11 @@ const TaskCard = forwardRef<HTMLDivElement, TaskCardProps>(
                     </Badge>
                   )}
 
-                  {/* Statut terminé */}
+                  {/* Statut terminé avec date de résolution */}
                   {completedAt && (
-                    <span className="text-emerald-400 font-mono font-bold">
-                      ✓ DONE
+                    <span className="text-emerald-400 font-mono font-bold flex items-center gap-1">
+                      <span>✓</span>
+                      <span>{formatDateForDisplay(completedAt, 'DISPLAY_SHORT')}</span>
                     </span>
                   )}