fn load_tera() -> Result<Tera>Expand description
Load the Tera instance for this builder invocation.
Checks whether .abbaye/theme/markdown.html.j2 exists and loads that
file when present; otherwise falls back to the compiled-in
TEMPLATE_MARKDOWN constant — exactly the same override mechanism
used by the site templates (root_index.html.j2 / version_index.html.j2).