try fix sonarr

code/Data/DataContext.cs

@@ -58,6 +58,15 @@ public class DataContext : DbContext
             entity.ComplexProperty(e => e.ContentBlocker);
         });
         
+        // Configure ArrConfig -> ArrInstance relationship
+        modelBuilder.Entity<ArrConfig>(entity =>
+        {
+            entity.HasMany(a => a.Instances)
+                  .WithOne(i => i.ArrConfig)
+                  .HasForeignKey(i => i.ArrConfigId)
+                  .OnDelete(DeleteBehavior.Cascade);
+        });
+        
         foreach (var entityType in modelBuilder.Model.GetEntityTypes())
         {
             var enumProperties = entityType.ClrType.GetProperties()

code/Data/Migrations/Data/20250615190608_InitialData.Designer.cs

@@ -12,7 +12,7 @@ using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
 namespace Data.Migrations.Data
 {
     [DbContext(typeof(DataContext))]
-    [Migration("20250615170420_InitialData")]
+    [Migration("20250615190608_InitialData")]
     partial class InitialData
     {
         /// <inheritdoc />

code/Data/Migrations/Data/20250615190608_InitialData.cs

@@ -202,7 +202,7 @@ namespace Data.Migrations.Data
                         principalTable: "download_cleaner_configs",
                         principalColumn: "id");
                 });
-
+            
             migrationBuilder.InsertData(
                 table: "queue_cleaner_configs",
                 columns: new[]

code/Data/Models/Configuration/Arr/ArrInstance.cs

@@ -12,7 +12,7 @@ public sealed class ArrInstance
     
     public Guid ArrConfigId { get; set; }
     
-    public ArrConfig ArrConfig { get; set; }
+    public ArrConfig? ArrConfig { get; set; }
     
     public required string Name { get; set; }