Imgui test engine cant find BeginChildEx because of '/'

BeginChildEx cant be found because the child window name contains a '/'. If I change these lines in BegindChildEx:

    if (name)
        ImFormatStringToTempBuffer(&temp_window_name, NULL, "%s/%s_%08X", parent_window->Name, name, id);
    else
        ImFormatStringToTempBuffer(&temp_window_name, NULL, "%/%08X", parent_window->Name, id);

to

    if (name)
        ImFormatStringToTempBuffer(&temp_window_name, NULL, "%s_%s_%08X", parent_window->Name, name, id);
    else
        ImFormatStringToTempBuffer(&temp_window_name, NULL, "%s_%08X", parent_window->Name, id);

i.e replace the slash with an underscore then ImGuiTestContext::ItemInfo can find the child window and doesn't chop off the name_id part.

ImGuiTestItemInfo ImGuiTestContext::ItemInfo(ImGuiTestRef ref, ImGuiTestOpFlags flags)

This is important for scrolling as otherwise items off screen in child windows can't be found as the current work around of serarching via **/name doesn't work.

This has allowed me to do this to scroll the item onto screen in the test framework:

		ImGuiWindow* window = ImGui::FindWindowByName(file_dialog);

		constexpr const char* child = "##files";

		ImGuiID id = window->GetID(child);

		std::string  child_name = std::format("{}_{}_{:08X}", file_dialog, child, id);

		ctx.SetRef(child_name.c_str());

		ctx.ScrollToItemY(std::format("##folder_{}", folder).c_str());

There is also a line in
ImGuiTestItemInfo ImGuiTestContext::WindowInfo(ImGuiTestRef ref, ImGuiTestOpFlags flags)
that needs to be changed here:

                ImGuiID child_window_id = 0;
                ImGuiWindow* child_window = NULL;
                {
                    // Child: Attempt 1: Try to BeginChild(const char*) variant and mimic its logic.
                    Str128 child_window_full_name;
#if (IMGUI_VERSION_NUM >= 18996) && (IMGUI_VERSION_NUM < 18999)
                    if (window_idstack_back == window->ID)
                    {
                        child_window_full_name.setf("%s/%s", window->Name, part_name.c_str());
                    }
                    else
#endif
                    {
                        ImGuiID child_item_id = GetID(part_name.c_str(), window_idstack_back);
****                        child_window_full_name.setf("%s_%s_%08X", window->Name, part_name.c_str(), child_item_id);  ****

Start with the BeginChildEx name construction and the ImGuiTestContext::ItemInfo and WindowInfo functions mentioned in the issue. Trace how child-window names are built and parsed, then verify that child windows containing '/' can be found and that off-screen items in them can be scrolled into view.