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/meetings.html

@@ -18,6 +18,9 @@
 <div class="card mt-3">
     {% for item in items %}
     <div class="list-row">
+        {% with reorder_url="/meetings/reorder", item_id=item.id %}
+        {% include 'partials/reorder_arrows.html' %}
+        {% endwith %}
         <span class="row-title"><a href="/meetings/{{ item.id }}">{{ item.title }}</a></span>
         <span class="row-meta">{{ item.meeting_date }}</span>
         {% if item.location %}