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/tasks.html

@@ -53,6 +53,9 @@
 <div class="card">
     {% for item in items %}
     <div class="list-row {{ 'completed' if item.status in ['done', 'cancelled'] }} {{ 'timer-active' if running_task_id and item.id|string == running_task_id }}">
+        {% with reorder_url="/tasks/reorder", item_id=item.id %}
+        {% include 'partials/reorder_arrows.html' %}
+        {% endwith %}
         <div class="row-check">
             <form action="/tasks/{{ item.id }}/toggle" method="post" style="display:inline">
                 <input type="checkbox" id="check-{{ item.id }}" {{ 'checked' if item.status == 'done' }}