Inline thinking bubbles with summary/full modes (#18033)

Co-authored-by: Jacob Richman <jacob314@gmail.com>

packages/cli/src/ui/utils/inlineThinkingMode.ts

@@ -0,0 +1,15 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import type { LoadedSettings } from '../../config/settings.js';
+
+export type InlineThinkingMode = 'off' | 'full';
+
+export function getInlineThinkingMode(
+  settings: LoadedSettings,
+): InlineThinkingMode {
+  return settings.merged.ui?.inlineThinkingMode ?? 'off';
+}