{#- chirp-ui: SPA-style link for content areas
    Opt-in navigation link with explicit HTMX attributes for SPA transitions.
    Use for pagination, breadcrumbs, or interlinked content pages that should
    swap without a full page reload.

    Uses hx-boost on the link itself so the server receives HX-Boosted and
    renders the page_block (not the narrow fragment). Boost on a leaf <a>
    element cannot leak to children.

    Plain <a> tags work fine for most links. Use nav_link only when you want
    the smooth SPA transition effect within the app shell.

    Usage:
        {% from "chirpui/nav_link.html" import nav_link %}

        {{ nav_link("/page-2", "Next page") }}

        {% call nav_link("/details") %}View details{% end %}
-#}

{% def nav_link(href, label="", cls="") %}
<a class="{{ cls }}"
   href="{{ href }}"
   hx-boost="true"
   hx-target="#main"
   hx-swap="innerHTML transition:true">{% if label %}{{ label }}{% else %}{% slot %}{% end %}</a>
{% end %}