Add families list, member kind filter, sidebar counters, pagination

New Families list page (parents/children columns, edit goes to the
detail view). Members list gets a member/guardian/both filter so
guardians aren't just invisible. Sidebar now shows live counts for
pending parent claims and games missing a referee, always numeric.
Member, event, team, group, news and family lists are paginated with
a shared pager partial that preserves the query string.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

management/templates/management/group_list.html

@@ -43,6 +43,8 @@
         </div>
     </div>
 
+    {% include "management/_pagination.html" %}
+
     {% trans "Delete group" as delete_group_title %}
     {% trans "Delete" as delete_label %}
     {% for group in groups %}