Say which font the labels are drawn with

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Vunz4VLxAYDBnU5tLciLDC

app/templates/admin/labels/settings.html

@@ -174,6 +174,36 @@
     </div>
 
     <div class="col-lg-5">
+        <div class="card mb-3">
+            <div class="card-header"><strong>Label font</strong></div>
+            <div class="card-body">
+                {% if font_info.kind == 'system' %}
+                <p class="mb-1 text-success small">
+                    <i class="bi bi-check-circle"></i> Labels are drawn with
+                    <strong>{{ font_info.name }}</strong>.
+                </p>
+                <p class="small text-muted mb-0">{{ font_info.path }}</p>
+                {% elif font_info.scalable %}
+                <p class="mb-1 small"><span class="badge bg-warning text-dark">Fallback</span>
+                    No system font found, so labels use {{ font_info.name }}.</p>
+                <p class="small text-muted mb-0">
+                    It prints at the right size, but a real font looks better:
+                    <code>apt install fonts-dejavu-core</code> on the server, or set
+                    <code>LABEL_FONT</code> to a .ttf file and restart.
+                </p>
+                {% else %}
+                <p class="mb-1 small"><span class="badge bg-danger">Broken</span>
+                    No scalable font on this server.</p>
+                <p class="small text-muted mb-0">
+                    Labels will print about a millimetre tall whatever <em>Text size</em>
+                    says, because Pillow's built-in font ignores the size asked for.
+                    Install <code>fonts-dejavu-core</code>, or point
+                    <code>LABEL_FONT</code> at a .ttf file, and restart.
+                </p>
+                {% endif %}
+            </div>
+        </div>
+
         <div class="card">
             <div class="card-header"><strong>PDF export</strong></div>
             <div class="card-body">