{#- Breadcrumb trail (T-2009, arc-007 S2b). Rendered inside #content (full loads
    via _wrapper.html, htmx loads via render_page prepend) so it stays fresh on
    every navigation. `breadcrumb` is a list of (label, url|None); url=None renders
    plain text (the current page or a non-link group). Empty list → nothing. -#}
{%- if breadcrumb %}
<nav class="wt-breadcrumb" aria-label="Breadcrumb">
  {%- for label, url in breadcrumb -%}
    {%- if not loop.first %}<span class="wt-breadcrumb-sep" aria-hidden="true">›</span>{% endif -%}
    {%- if url %}<a href="{{ url }}" hx-target="#content" hx-swap="innerHTML" hx-push-url="true">{{ label }}</a>
    {%- else %}<span{% if loop.last %} aria-current="page"{% endif %}>{{ label }}</span>{% endif -%}
  {%- endfor -%}
  {#- Pin toggle (T-2010, arc-007 S2c) — pushed to the right on pinnable nav pages. -#}
  {%- if wt_pinnable %}<span class="wt-breadcrumb-spacer"></span>{% include "_star.html" %}{% endif -%}
</nav>
{%- endif %}