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/partials/reorder_arrows.html

@@ -0,0 +1,30 @@
+{#
+  Reorder grip handle. Include with:
+    {% with reorder_url="/focus/reorder", item_id=item.id %}
+    {% include 'partials/reorder_arrows.html' %}
+    {% endwith %}
+
+  Required context vars:
+    reorder_url  - POST endpoint for the reorder action
+    item_id      - ID of the current item
+  Optional:
+    extra_fields - dict of extra hidden fields (e.g. {"focus_date": "2026-03-03"})
+#}
+<span class="reorder-grip">
+    <form action="{{ reorder_url }}" method="post">
+        <input type="hidden" name="item_id" value="{{ item_id }}">
+        <input type="hidden" name="direction" value="up">
+        {% if extra_fields %}{% for k, v in extra_fields.items() %}
+        <input type="hidden" name="{{ k }}" value="{{ v }}">
+        {% endfor %}{% endif %}
+        <button type="submit" class="grip-btn" title="Move up">⠛</button>
+    </form>
+    <form action="{{ reorder_url }}" method="post">
+        <input type="hidden" name="item_id" value="{{ item_id }}">
+        <input type="hidden" name="direction" value="down">
+        {% if extra_fields %}{% for k, v in extra_fields.items() %}
+        <input type="hidden" name="{{ k }}" value="{{ v }}">
+        {% endfor %}{% endif %}
+        <button type="submit" class="grip-btn" title="Move down">⠓</button>
+    </form>
+</span>