feat: add miller document layout

apps/server/internal/markdown/renderer.go

@@ -15,7 +15,8 @@ import (
 )
 
 var (
-	tagPattern = regexp.MustCompile(`(^|[\s(])#([a-zA-Z0-9_-]+)\b`)
+	tagPattern     = regexp.MustCompile(`(^|[\s(])#([a-zA-Z0-9_-]+)\b`)
+	firstH1Pattern = regexp.MustCompile(`(?s)^\s*<h1\b[^>]*>.*?</h1>\s*`)
 )
 
 type Result struct {
@@ -61,8 +62,10 @@ func (r *Renderer) Render(content []byte) (Result, error) {
 		return Result{}, fmt.Errorf("render markdown: %w", err)
 	}
 
+	html := firstH1Pattern.ReplaceAllString(output.String(), "")
+
 	return Result{
-		HTML:  template.HTML(output.String()),
+		HTML:  template.HTML(html),
 		Title: title,
 		Tags:  tags,
 	}, nil