// A user message not followed by assistant is treated as standalone turn
        final List<LlmMessage> history = new ArrayList<>();
        history.add(LlmMessage.user("Q1")); // 2 - standalone
        history.add(LlmMessage.user("Q2")); // 2 - standalone (no preceding assistant)
        final LlmChatRequest request = new LlmChatRequest();

#     rbe_linux:                      General RBE options used on all linux builds.
#     rbe_win_base:                   General RBE options used on all Windows builds. Not to be used standalone.
#     rbe_windows_x86_cpu_2022:       Windows-specific RBE options.
#
#     rbe_linux_cpu:                  RBE options to build with only CPU support.

        if (history.isEmpty()) {
            return;
        }

        // Build turn list: group adjacent user-assistant pairs as turns, standalone messages as single-message turns
        final List<int[]> turns = new ArrayList<>();
        int idx = 0;
        while (idx < history.size()) {