feat(11-01): remove checkbox-disable restrictions for future tasks

- Remove isFuture guard in calendar_day_list.dart, pass canComplete: true always
- Remove isFuture check in task_row.dart, always enable Checkbox.onChanged
- calendar_task_row.dart unchanged (canComplete param already defaults to true)

lib/features/home/presentation/calendar_day_list.dart

@@ -240,9 +240,6 @@ class _CalendarDayListState extends ConsumerState<CalendarDayList> {
     AppLocalizations l10n,
     ThemeData theme,
   ) {
-    final now = DateTime.now();
-    final today = DateTime(now.year, now.month, now.day);
-    final isFuture = state.selectedDate.isAfter(today);
     final showRoomTag = widget.roomId == null;
 
     final items = <Widget>[];
@@ -268,7 +265,7 @@ class _CalendarDayListState extends ConsumerState<CalendarDayList> {
         tw,
         isOverdue: false,
         showRoomTag: showRoomTag,
-        canComplete: !isFuture,
+        canComplete: true,
       ));
     }
 

lib/features/tasks/presentation/task_row.dart

@@ -42,7 +42,6 @@ class TaskRow extends ConsumerWidget {
       task.nextDueDate.day,
     );
     final isOverdue = dueDate.isBefore(today);
-    final isFuture = dueDate.isAfter(today);
 
     // Format relative due date in German
     final relativeDateText = formatRelativeDate(task.nextDueDate, now);
@@ -57,9 +56,7 @@ class TaskRow extends ConsumerWidget {
     return ListTile(
       leading: Checkbox(
         value: false, // Always unchecked -- completion is immediate + reschedule
-        onChanged: isFuture
-            ? null // Future tasks cannot be completed yet
-            : (_) {
+        onChanged: (_) {
           // Mark done immediately (optimistic UI, no undo per user decision)
           ref.read(taskActionsProvider.notifier).completeTask(task.id);
         },