feat: implement commission calculation strategy with ORM and SP options

src/CMSMicroservice.Application/NetworkMembershipCQ/Queries/GetNetworkStatistics/GetNetworkStatisticsQueryHandler.cs

@@ -56,16 +56,20 @@ public class GetNetworkStatisticsQueryHandler : IRequestHandler<GetNetworkStatis
 
         // Monthly growth (last 6 months) - using Created date
         var sixMonthsAgo = DateTime.Now.AddMonths(-6);
-        var monthlyGrowth = await _context.Users
+        var monthlyGrowthRaw = await _context.Users
             .Where(x => x.NetworkParentId != null && x.Created >= sixMonthsAgo)
-            .GroupBy(x => new { x.Created.Year, x.Created.Month })
+            .Select(x => new { x.Created.Year, x.Created.Month })
+            .ToListAsync(cancellationToken);
+
+        var monthlyGrowth = monthlyGrowthRaw
+            .GroupBy(x => new { x.Year, x.Month })
             .Select(g => new MonthlyGrowthModel
             {
                 Month = $"{g.Key.Year}-{g.Key.Month:D2}",
                 NewMembers = g.Count()
             })
             .OrderBy(x => x.Month)
-            .ToListAsync(cancellationToken);
+            .ToList();
 
         // Top users by total children count
         var topUsers = await _context.Users