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_integration_test.go

@@ -0,0 +1,68 @@
+//go:build integration
+
+package fetch_test
+
+import (
+	"context"
+	"os"
+	"testing"
+
+	"github.com/eslider/go-onlyoffice/cmd/office/model"
+)
+
+func TestIntegrationUpdateTaskTitleDescription(t *testing.T) {
+	loader, ctx := liveLoader(t)
+	items, err := loader.List(ctx, model.ListSpec{Subject: model.SubjectTasks})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(items) == 0 {
+		t.Skip("no tasks")
+	}
+	item := items[0]
+	title, desc, err := loader.TaskFields(ctx, item)
+	if err != nil {
+		t.Fatal(err)
+	}
+	restoreTitle, restoreDesc := title, desc
+	t.Cleanup(func() {
+		_ = loader.UpdateTask(context.Background(), item.ID, restoreTitle, restoreDesc)
+	})
+	newTitle := title + " (office TUI test)"
+	newDesc := desc + "\n\n_edited by office integration test_"
+	if err := loader.UpdateTask(ctx, item.ID, newTitle, newDesc); err != nil {
+		t.Fatal(err)
+	}
+	gotTitle, gotDesc, err := loader.TaskFields(ctx, item)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if gotTitle != newTitle {
+		t.Fatalf("title: got %q want %q", gotTitle, newTitle)
+	}
+	if gotDesc != newDesc {
+		t.Fatalf("description mismatch")
+	}
+}
+
+func TestIntegrationTaskFieldsFromLiveAPI(t *testing.T) {
+	if os.Getenv("ONLYOFFICE_URL") == "" && os.Getenv("ONLYOFFICE_HOST") == "" {
+		t.Skip("ONLYOFFICE_URL not set")
+	}
+	loader, ctx := liveLoader(t)
+	items, err := loader.List(ctx, model.ListSpec{Subject: model.SubjectTasks})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(items) == 0 {
+		t.Skip("no tasks")
+	}
+	title, desc, err := loader.TaskFields(ctx, items[0])
+	if err != nil {
+		t.Fatal(err)
+	}
+	if title == "" {
+		t.Fatal("empty title")
+	}
+	_ = desc
+}