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/language/en-GB/tpl_mokocassiopeia.ini

@@ -66,6 +66,7 @@ TPL_MOKOCASSIOPEIA_FONT_NOTE_TEXT="Loading fonts from external sources might be
 ; ===== Header & navigation (Theme tab) =====
 TPL_MOKOCASSIOPEIA_STICKY_LABEL="Sticky Header"
 TPL_MOKOCASSIOPEIA_BACKTOTOP="Back to Top"
+TPL_MOKOCASSIOPEIA_TOC_TITLE="Table of Contents"
 TPL_MOKOCASSIOPEIA_BACKTOTOP_LABEL="Back-to-top Link"
 TPL_MOKOCASSIOPEIA_TOC="Table of Contents"
 

src/language/en-US/tpl_mokocassiopeia.ini

@@ -66,6 +66,7 @@ TPL_MOKOCASSIOPEIA_FONT_NOTE_TEXT="Loading fonts from external sources might be
 ; ===== Header & navigation (Theme tab) =====
 TPL_MOKOCASSIOPEIA_STICKY_LABEL="Sticky Header"
 TPL_MOKOCASSIOPEIA_BACKTOTOP="Back to Top"
+TPL_MOKOCASSIOPEIA_TOC_TITLE="Table of Contents"
 TPL_MOKOCASSIOPEIA_BACKTOTOP_LABEL="Back-to-top Link"
 TPL_MOKOCASSIOPEIA_TOC="Table of Contents"