Adds new hook_localgov_publications_menu_tree_alter() hook.

[rupertj]

No description provided.

[rupertj]

For a quick example of what this is for, we use this on H&F to show a different shorter title in the menu block to the node title.

EG: https://www.lbhf.gov.uk/publications/corporate-plan/hf-plan-2023-2026

"About" in the menu has the node title "About this plan".
"Our borough" in the menu has the node title "Our borough at a glance".
etc...

To do this, we use a field that we've added to most content types called field_lbhf_teaser_title, which is used anywhere we need a shorter title.

The code to swop it over that uses the hook in this PR looks like this:

/**
 * Implements hook_localgov_publications_menu_tree_alter().
 *
 * Sets the menu link title for publication pages to the teaser title, if set.
 */
function lbhf_core_localgov_publications_menu_tree_alter(&$tree) {
  foreach ($tree as $item) {
    if (!empty($item['below'])) {
      lbhf_core_localgov_publications_menu_tree_alter($item['below']);
    }

    if (!isset($item['link']['nid'])) {
      continue;
    }

    $node = Node::load($item['link']['nid']);

    if (!$node instanceof NodeInterface) {
      continue;
    }

    if (!$node->hasField('field_lbhf_teaser_title')) {
      continue;
    }

    $teaserTitle = $node->get('field_lbhf_teaser_title')->value;
    if ($teaserTitle) {
      $item['link']['title'] = $teaserTitle;
    }
  }
}

[finnlewis]

Looks like a useful thing, but I don't think I've ever written a hook.

Flagging for @ekes, @stephen-cox or @andybroomfield to take a look for awareness as much as anything.

[rupertj]

@andybroomfield Implementing this hook in a theme works for me now. Care to re-review it? :)

[andybroomfield]

Working for me also, thanks.