Optimize loop structure in hook_node_grants()

Problem/Motivation

node_view_permissions_node_grants() has several loop inefficiencies that compound on multilingual sites with many content types:

1. NodeType::loadMultiple() called inside the language loop. With 8 languages, all content type entities are loaded 8 times instead of once.
2. hasPermission() called redundantly per language. Permission results depend on the user's roles, not the language. With 8 languages and 17 types, this means ~540 redundant permission checks per invocation.
3. Language-independent grants set inside the language loop. Grants like view_any_{type}_content are identical across languages but are redundantly assigned on every language iteration.
4. Unused variables. $node = \Drupal::routeMatch()->getParameter('node') and $language_manager are assigned but never used.

Related: #3571280 proposes removing language-specific grants entirely. This issue takes a less invasive approach — keeping the same grant output but restructuring the loops to avoid redundant work.

Steps to reproduce

1. Install node_view_permissions on a multilingual site (e.g., 8 languages, 17+ content types).
2. Profile node_view_permissions_node_grants() with Xdebug/Blackfire.
3. Observe NodeType::loadMultiple() called once per language, and hasPermission() called 4× per language/type combination instead of 4× per type.

Proposed resolution

Restructure the loops so that:

• NodeType::loadMultiple() is called once, before any loop.
• hasPermission() results are computed once per content type (outer loop), then reused in the language loop (inner loop).
• Language-independent grants are set in the outer loop, language-specific grants in the inner loop.
• Unused variables are removed.

$result = [];
if ($op == 'view') {
  $languages = \Drupal::languageManager()->getLanguages();
  $node_types = NodeType::loadMultiple();
  foreach ($node_types as $type) {
    $type_id = $type->id();
    $view_any = $account->hasPermission("view any $type_id content");
    $view_own = $account->hasPermission("view own $type_id content");
    $view_any_unpublished = $account->hasPermission("view any unpublished content");
    $view_own_unpublished = $account->hasPermission("view own unpublished content");

    // Language-independent grants (set once per type).
    if ($view_any) {
      $result["view_any_{$type_id}_content"] = [1];
    }
    if ($view_own) {
      $result["view_own_{$type_id}_content"] = [$account->id()];
    }
    if ($view_any_unpublished && $view_any) {
      $result["view_any_unpublished_{$type_id}_content"] = [1];
    }
    if ($view_own_unpublished && $view_own) {
      $result["view_own_unpublished_{$type_id}_content"] = [$account->id()];
    }

    // Language-specific grants (reuse cached permission results).
    foreach ($languages as $langcode => $language) {
      if ($view_any) {
        $result["view_any_{$type_id}_{$langcode}_content"] = [1];
      }
      if ($view_own) {
        $result["view_own_{$type_id}_{$langcode}_content"] = [$account->id()];
      }
      if ($view_any_unpublished && $view_any) {
        $result["view_any_unpublished_{$type_id}_{$langcode}_content"] = [1];
      }
      if ($view_own_unpublished && $view_own) {
        $result["view_own_unpublished_{$type_id}_{$langcode}_content"] = [$account->id()];
      }
    }
  }
}

The output is identical — same grants, same keys, same values. Only the execution path changes.

Remaining tasks

• Review and test the patch.
• Verify grant output is byte-identical before and after.