feat(cli): implement prompt stashing with Alt+S

packages/cli/src/test-utils/render.tsx

@@ -567,6 +567,8 @@ const mockUIActions: UIActions = {
   handleEmptyWalletChoice: vi.fn(),
   setQueueErrorMessage: vi.fn(),
   popAllMessages: vi.fn(),
+  stashPrompt: vi.fn(),
+  popStashedPrompt: vi.fn(),
   handleApiKeySubmit: vi.fn(),
   handleApiKeyCancel: vi.fn(),
   setBannerVisible: vi.fn(),