fix(chart): show correct chart type in previews

- Use NoteChart directly with props instead of NoteChartFromCode
- Remove markdown ticks from chartSuggestionToMarkdown output
- Export NoteChart component for direct use in previews

Now the 3 suggestions correctly show different chart types.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

memento-note/lib/ai/services/chart-suggestion.service.ts

@@ -71,9 +71,10 @@ export async function suggestCharts(request: SuggestChartsRequest): Promise<Sugg
 }
 
 /**
- * Convert a chart suggestion to markdown code block format
+ * Convert a chart suggestion to raw chart format (no markdown ticks)
+ * This is the content that goes inside <code class="language-chart">
  * @param suggestion - The chart suggestion to convert
- * @returns Markdown code block string
+ * @returns Raw chart content string
  */
 export function chartSuggestionToMarkdown(suggestion: ChartSuggestion): string {
   const lines = [
@@ -81,5 +82,5 @@ export function chartSuggestionToMarkdown(suggestion: ChartSuggestion): string {
     suggestion.title,
     ...suggestion.data.map(d => `${d.label}: ${d.value}`),
   ]
-  return `\`\`\`chart\n${lines.join('\n')}\n\`\`\``
+  return lines.join('\n')
 }