fix(TaskFormDialog): control Due popover open state for keyboard close

Add dueOpen state + onOpenChange so Esc and outside-click close the
popover consistently with the other pills; wire DateField.onCommit
to close the popover after Enter or calendar click.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

src/renderer/components/tasks/TaskFormDialog.tsx

@@ -318,6 +318,7 @@ export function TaskFormDialog({
   const [priorityOpen, setPriorityOpen] = useState(false);
   const [statusOpen, setStatusOpen] = useState(false);
   const [assigneesOpen, setAssigneesOpen] = useState(false);
+  const [dueOpen, setDueOpen] = useState(false);
   const [creatingProject, setCreatingProject] = useState(false);
   const [assigneeInput, setAssigneeInput] = useState('');
 
@@ -333,6 +334,7 @@ export function TaskFormDialog({
       setPriorityOpen(false);
       setStatusOpen(false);
       setAssigneesOpen(false);
+      setDueOpen(false);
     }
   }, [open, initialValues]);
 
@@ -502,7 +504,7 @@ export function TaskFormDialog({
               </Popover>
 
               {/* Due date */}
-              <Popover>
+              <Popover open={dueOpen} onOpenChange={setDueOpen}>
                 <PopoverTrigger asChild>
                   <PropertyPill
                     {...pillsRoving.getItemProps(3)}
@@ -519,6 +521,7 @@ export function TaskFormDialog({
                     withTime
                     value={values.dueDate ? new Date(values.dueDate) : undefined}
                     onChange={(d) => setValues((v) => ({ ...v, dueDate: d ? d.getTime() : null }))}
+                    onCommit={() => setDueOpen(false)}
                     placeholder={t('tasks.colDue')}
                     aria-label={t('tasks.colDue')}
                   />