feat: universal reorder grip handles and compact UI density

- Add generic move_in_order() to BaseRepository for reorder support
- Add reusable reorder_arrows.html partial with grip dot handles
- Add reorder routes to all 9 list routers (tasks, notes, links, contacts, meetings, decisions, appointments, lists, focus)
- Compact row padding (6px 12px, gap 8px) on .list-row and .focus-item
- Reduce font size to 0.80rem on row titles, sidebar nav, domain tree

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

templates/contacts.html

@@ -8,6 +8,9 @@
 <div class="card">
 {% for item in items %}
 <div class="list-row">
+    {% with reorder_url="/contacts/reorder", item_id=item.id %}
+    {% include 'partials/reorder_arrows.html' %}
+    {% endwith %}
     <span class="row-title"><a href="/contacts/{{ item.id }}">{{ item.first_name }} {{ item.last_name or '' }}</a></span>
     {% if item.company %}<span class="row-tag">{{ item.company }}</span>{% endif %}
     {% if item.role %}<span class="row-meta">{{ item.role }}</span>{% endif %}