feat(webui): centralize disabled button reasons

webui/tests/data-grid-actions.test.tsx

@@ -3,6 +3,7 @@ function assertEqual<T>(actual: T, expected: T, message: string): void {
 }
 
 import { renderToStaticMarkup } from "react-dom/server";
+import Button from "../src/components/Button";
 import { DataGridEmptyAction, DataGridRowActions } from "../src/components/table/DataGrid";
 import TableActionGroup, { runTableAction } from "../src/components/table/TableActionGroup";
 
@@ -60,3 +61,8 @@ const noReorderActions = renderToStaticMarkup(
   <DataGridRowActions onAddBelow={noop} onRemove={noop} />
 );
 assertEqual(buttonCount(noReorderActions), 2, "row actions omit reorder controls when ordering does not apply");
+
+const reasonedButton = renderToStaticMarkup(<Button disabledReason="Permission denied">Save</Button>);
+assertEqual(reasonedButton.includes("disabled=\"\""), true, "a disabled reason disables the central button");
+assertEqual(reasonedButton.includes("disabled-action-tooltip"), true, "a disabled reason remains keyboard discoverable");
+assertEqual(reasonedButton.includes("disabledReason"), false, "the central-only disabled reason is not passed to the DOM");