fix context sentences in YAML to ensure vocab emphasis

docs/.vitepress/theme/components/VocabQuiz.vue

@@ -146,7 +146,7 @@ import {
 import yaml from "yaml";
 import SentenceAudio from "./SentenceAudio.vue";
 import { supabase } from "../supabase.ts";
-import { IVoc, Voc } from "../types.ts";
+import { fmValueParser, IVoc, Voc } from "../types.ts";
 import { LLMstream } from "../llm.ts";
 import MarkdownIt from "markdown-it";
 
@@ -263,7 +263,7 @@ watch(sent_ko, () => {
 const vocabulary: Record<string, IVoc[]> = {};
 
 for (const [k, vs] of Object.entries(
-  frontmatter.value[fmKey] as Record<string, IVoc[]>,
+  fmValueParser.parse(frontmatter.value[fmKey]),
 )) {
   vocabulary[k] = [...(vocabulary[k] || []), ...vs];