Scope TOC to article body only and use language string for title

- Move data-toc-scope from outer column to .article-content div so
  the TOC only sees headings inside the article body, ignoring page
  headers and article titles.
- Pass $scope explicitly in the JS auto-init so headings outside the
  article content are never picked up.
- Replace hardcoded article title in TOC heading with a
  TPL_MOKOCASSIOPEIA_TOC_TITLE language string ("Table of Contents").
- Add Text use statement to both toc-left.php and toc-right.php.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/media/vendor/bootstrap-toc/bootstrap-toc.js

@@ -178,7 +178,8 @@
   $(function() {
     $('nav[data-toggle="toc"]').each(function(i, el) {
       var $nav = $(el);
-      Toc.init($nav);
+      var $scope = $('[data-toc-scope]');
+      Toc.init({ $nav: $nav, $scope: $scope.length ? $scope : $(document.body) });
     });
   });
 })(jQuery);