Refactor ErrorAction to use enum for type safety

Changed RecActionDto.ErrorAction from string to ErrorAction enum, updating all related logic to use enum values instead of strings. Added necessary using directives. This improves type safety, reduces risk of typos, and enhances maintainability.

src/ReC.Application/RecActions/Commands/InvokeBatchRecActionsCommand.cs

@@ -1,5 +1,6 @@
 using MediatR;
 using ReC.Application.RecActions.Queries;
+using ReC.Domain.Constants;
 
 namespace ReC.Application.RecActions.Commands;
 
@@ -21,9 +22,9 @@ public class InvokeRecActionsCommandHandler(ISender sender) : IRequestHandler<In
         {
             var ok = await sender.Send(action.ToInvokeCommand(), cancel);
             if (!ok)
-                switch (action.ErrorAction?.ToLowerInvariant())
+                switch (action.ErrorAction)
                 {
-                    case "continue":
+                    case ErrorAction.Continue:
                         break;
                     default:
                         return;