chore(codebase): full cleanup pass

backend/Modules/Memberships/Handlers/GetActiveMemberships.cs

@@ -28,16 +28,16 @@ public class GetActiveMembershipsHandler(
     public override async Task HandleAsync(
         CancellationToken ct)
     {
-        var subscriptions = await dbContext
+        List<Membership> subscriptions = await dbContext
             .Memberships
             .Where(subscription => subscription.UserId == User.GetUserId())
             .Where(subscription => subscription.State == MembershipState.Active)
             .ToListAsync(ct);
 
-        var result = await Task.WhenAll(
+        GetActiveMembershipsResponse[] result = await Task.WhenAll(
             subscriptions.Select(async subscription =>
             {
-                var creator = await creatorLookup.GetCreatorAsync(subscription.CreatorId, ct);
+                CreatorReference? creator = await creatorLookup.GetCreatorAsync(subscription.CreatorId, ct);
 
                 return new GetActiveMembershipsResponse(
                     subscription.Id,