Fix loose-list rendering when list items are wrapped in paragraphs

[yukihane]

Summary

This PR fixes a list rendering issue when Markdown is parsed as a loose list (<li><p>...</p></li>).

The theme renders list bullets using ul > li::before with hanging indent.
When list item content is wrapped in <p>, bullet and text can appear visually split.

Changes

• Add a targeted CSS rule in assets/css/main.css:

  ul li > p:first-child {
    display: inline;
    margin: 0;
  }

• Add a minimal reproduction page in exampleSite/content/posts/loose-list-rendering.md
  to compare tight vs loose list rendering.

Scope

• No theme API changes
• No required content migration for existing users
• CSS-only rendering fix