Change section with li

current-output.html

<p>Independent paragraph.</p>
<section id="my-heading-1" class="level1">
  <h1>My heading 1</h1>
  <p>Para in heading 1.</p>
  <section id="my-heading-2" class="level2">
    <h2>My heading 2</h2>
    <p>Para in heading 2</p>
  </section>
</section>
<section id="another-heading-1" class="level1">
  <h1>Another heading 1</h1>
  <p>With its own para.</p>
</section>

desired-output.html

<p>Independent paragraph.</p>
<ol>
  <li id="my-heading-1" class="level1">
    <h1>My heading 1</h1>
    <p>Para in heading 1.</p>
    <ol>
      <li id="my-heading-2" class="level2">
        <h2>My heading 2</h2>
        <p>Para in heading 2</p>
      </li>
    </ol>
  </li>
  <li id="another-heading-1" class="level1">
    <h1>Another heading 1</h1>
    <p>With its own para.</p>
  </li>
</ol>

source.txt

Independent paragraph.

# My heading 1

Para in heading 1.

## My heading 2

Para in heading 2

# Another heading 1

With its own para.