feat(office): table detail panes and Alt+1/2/3 layout toggles

Add spreadsheet-style list, split detail pane with forms and document preview,
and Alt+1/2/3 to show/hide panes with even width distribution.

Co-authored-by: Cursor <cursoragent@cursor.com>

cmd/office/fetch/task.go

@@ -0,0 +1,36 @@
+package fetch
+
+import (
+	"context"
+	"fmt"
+	"strconv"
+
+	onlyoffice "github.com/eslider/go-onlyoffice"
+	"github.com/eslider/go-onlyoffice/cmd/office/model"
+)
+
+// UpdateTask saves title and description for a project task.
+func (l *Loader) UpdateTask(ctx context.Context, taskID, title, description string) error {
+	if l == nil || l.Client == nil {
+		return fmt.Errorf("fetch: client is nil")
+	}
+	id, err := strconv.Atoi(taskID)
+	if err != nil {
+		return fmt.Errorf("task id %q: %w", taskID, err)
+	}
+	_, err = l.Client.UpdateProjectTask(onlyoffice.ProjectTaskUpdateRequest{
+		ID:          id,
+		Title:       title,
+		Description: description,
+	})
+	return err
+}
+
+// TaskFields loads title and description for a project task item.
+func (l *Loader) TaskFields(ctx context.Context, item model.Item) (title, description string, err error) {
+	fields, err := l.DetailForm(ctx, item)
+	if err != nil {
+		return "", "", err
+	}
+	return fields.Primary, fields.Secondary, nil
+}