Add autoID for definition terms

Fixes #13403
See #11566

Co-authored-by: Joe Mooring <joe@mooring.com>

markup/goldmark/toc.go

@@ -53,6 +53,10 @@ func (t *tocTransformer) Transform(n *ast.Document, reader text.Reader, pc parse
 		headingText bytes.Buffer
 	)
 
+	if ids := pc.IDs().(stringValuesProvider).StringValues(); len(ids) > 0 {
+		toc.SetIdentifiers(ids)
+	}
+
 	ast.Walk(n, func(n ast.Node, entering bool) (ast.WalkStatus, error) {
 		s := ast.WalkStatus(ast.WalkContinue)
 		if n.Kind() == ast.KindHeading {
@@ -131,5 +135,7 @@ func (e *tocExtension) Extend(m goldmark.Markdown) {
 	r.AddOptions(e.options...)
 	m.Parser().AddOptions(parser.WithASTTransformers(util.Prioritized(&tocTransformer{
 		r: r,
-	}, 10)))
+	},
+		// This must run after the ID generation (priority 100).
+		110)))
 }