Function normalizeLanguage

src/core/nodeviews/code-block.ts:506–509

* 规范化语言名称

(language: string)

 * 规范化语言名称
 */
function normalizeLanguage(language: string): string {
  const lower = language.toLowerCase();
  return languageAliases[lower] || lower;
}

/**
 * 获取语言扩展