Slug joiner normalization

internal/topdata/wiki_native.go

@@ -1682,25 +1682,7 @@ func wikiPublicTarget(namespace, slug string) string {
 }
 
 func wikiSlugifyTitle(value string) string {
-	value = html.UnescapeString(strings.TrimSpace(value))
-	var b strings.Builder
-	lastDash := false
-	for _, r := range strings.ToLower(value) {
-		if (r >= 'a' && r <= 'z') || (r >= '0' && r <= '9') {
-			b.WriteRune(r)
-			lastDash = false
-			continue
-		}
-		if b.Len() > 0 && !lastDash {
-			b.WriteByte('-')
-			lastDash = true
-		}
-	}
-	slug := strings.Trim(b.String(), "-")
-	if slug == "" {
-		return "topic"
-	}
-	return slug
+	return slugifyWikiText(value, "topic")
 }
 
 func wikiPageIDToRelPath(pageID string) string {