Make InsertObjectProcedure properties nullable, require ResultType

Updated InsertObjectProcedure to make related command properties nullable and removed default initializations. Updated handler to use null-conditional access for these properties. Changed InsertResultCommand.Type to required and updated tests accordingly. Improves null safety and clarifies required fields.

src/ReC.Application/Results/Commands/InsertResultCommand.cs

@@ -12,7 +12,7 @@ public record InsertResultCommand : IInsertProcedure
     public string? Body { get; set; }
     public string? Info { get; set; }
     public string? Error { get; set; }
-    public ResultType? Type { get; set; }
+    public required ResultType Type { get; set; }
 }
 
 public class InsertResultProcedureHandler(ISender sender) : IRequestHandler<InsertResultCommand, long>