Update SearchScore and use AsParallel

Elwig/Windows/MemberAdminWindow.xaml.cs

@@ -72,7 +72,7 @@ namespace Elwig.Windows {
             List<Member> members = await memberQuery.ToListAsync();
 
             if (TextFilter.Count > 0) {
-                var dict = members
+                var dict = members.AsParallel()
                     .ToDictionary(m => m, m => m.SearchScore(TextFilter))
                     .OrderByDescending(a => a.Value)
                     .ThenBy(a => a.Key.FamilyName)