Use grid row components in page.html.twig

Problem/Motivation

Presenter templates must not have markup, only calls to components

page.html.twig is a presenter template with:

• calls to ui_suite_daisyui:navbar
• but some hardcoded duplication fo grid row markup

Snippet:

  <main role="main" class="grid grid-cols-12">
    {% if page.sidebar %}
    <div class="col-span-9">
      {{ page.content }}
    </div>
    <aside class="col-span-3" role="complementary">
      {{ page.sidebar }}
    </aside>
    {% else %}
    <div class="col-span-12">
      {{ page.content }}
    </div>
    {% endif %}
  </main>

It was not an issue before, but we have grid row components now.

Proposed resolution

Calling grid row component(s) in page template will have those benefits:

• check if our grid components work well in this real life scenario, and maybe improve or fix them
• be ready when page displays will be buildable (thanks to page manager, experience builder, or other...)

You may be interested by what was done in https://git.drupalcode.org/project/ui_suite_material/-/blob/2.0.x/templa...

And what will be done in Bootstrap theme: 📌 [5.1.x] Use grid row components in page.html.twig Active
And DSFR theme: 📌 [1.1.x] Use grid row components in page.html.twig Active

API changes

Maybe some additional props or mechanisms to grid SDC components, but nothing breaking.