Simplify CheckListOptions logic

Refactor `StaticCheckListOptionsProvider` to inherit from the new `CheckListOptionsProviderBase` and streamline checklist item generation logic.

src/apps/Elsa.Server.Web/Activities/CheckedActivity.cs

@@ -0,0 +1,19 @@
+using Elsa.Extensions;
+using Elsa.Workflows;
+using Elsa.Workflows.Attributes;
+using Elsa.Workflows.Models;
+using Elsa.Workflows.UIHints;
+using Elsa.Workflows.UIHints.CheckList;
+
+namespace Elsa.Server.Web.Activities;
+
+public class CheckedActivity : CodeActivity<string[]>
+{
+    [Input(UIHint = InputUIHints.CheckList, UIHandler = typeof(StaticCheckListOptionsProvider), Options = new[]{"A", "B", "C"})]
+    public Input<string[]> CheckedItems { get; set; }
+
+    protected override void Execute(ActivityExecutionContext context)
+    {
+        context.SetResult(CheckedItems.GetOrDefault(context));
+    }
+}

src/modules/Elsa.Workflows.Core/UIHints/CheckList/StaticCheckListOptionsProvider.cs

@@ -6,32 +6,22 @@ namespace Elsa.Workflows.UIHints.CheckList;
 /// <summary>
 /// Provides static drop-down options for a given property.
 /// </summary>
-public class StaticCheckListOptionsProvider : IPropertyUIHandler
+public class StaticCheckListOptionsProvider : CheckListOptionsProviderBase
 {
     /// <inheritdoc />
-    public ValueTask<IDictionary<string, object>> GetUIPropertiesAsync(PropertyInfo propertyInfo, object? context, CancellationToken cancellationToken = default)
+    protected override ValueTask<ICollection<CheckListItem>> GetItemsAsync(PropertyInfo propertyInfo, object? context, CancellationToken cancellationToken)
     {
         var inputAttribute = propertyInfo.GetCustomAttribute<InputAttribute>();
         var inputOptions = inputAttribute?.Options;
-        var dictionary = new Dictionary<string, object>();
 
         if (inputOptions == null)
-            return new(dictionary);
+            return new([]);
 
         var selectListItems = (inputOptions as ICollection<string>)?.Select(x => new CheckListItem(x, x)).ToList();
 
         if (selectListItems == null)
-            return new(dictionary);
-
-        var props = new CheckListProps
-        {
-            CheckList = new()
-            {
-                Items = selectListItems.ToList() 
-            }
-        };
-
-        dictionary[InputUIHints.CheckList] = props;
-        return new(dictionary);
+            return new([]);
+        
+        return new(selectListItems);
     }
 }