{#
  Shared page header (Phase 10.3). One consistent title/subtitle block for every
  dashboard/list page so switching between pages feels like the same template.

  Reference design: the Saved Items header — an <h1 class="h3 fw-bold"> title with
  a muted one-line subtitle. Uses Bootstrap utilities only, so the typography,
  weight, colour and spacing are pixel-identical everywhere it's used.

  Usage:
    {% from "components/page_header.html" import page_header %}
    {{ page_header('My Listings', "Items you've listed for sale.") }}
#}
{% macro page_header(title, subtitle=None) %}
  <div class="page-header mb-4">
    <h1 class="h3 fw-bold mb-1">{{ title }}</h1>
    {% if subtitle %}<p class="text-muted mb-0">{{ subtitle }}</p>{% endif %}
  </div>
{% endmacro %}