Fix JsonElement serialization error for ControlPropertyState in dynamic properties.

Add app with categoty and ControlPropertyState to test (RoundripTests)

Author: marcelbf

src/PAModel/IR/IRStateHelpers.cs

@@ -360,7 +360,7 @@ private static (Item item, int index) CombineIRAndState(BlockNode blockNode, Err
             foreach (var propIR in blockNode.Properties)
             {
                 // Dynamic properties could be null for the galleryTemplateTemplate                
-                var isDynamicProperty = state.DynamicProperties != null && 
+                var isDynamicProperty = state.DynamicProperties != null &&
                     ((isInResponsiveLayout && DynamicProperties.IsResponsiveLayoutProperty(propIR.Identifier)) ||
                     // Check if property is dynamic (responsive layout or has metadata like ControlPropertyState)
                     state.DynamicProperties.Any(dp => dp.PropertyName == propIR.Identifier));
@@ -380,7 +380,15 @@ private static (Item item, int index) CombineIRAndState(BlockNode blockNode, Err
                 // Add dummy dynamic output props in the state at the end
                 foreach (var dynPropState in state.DynamicProperties.Where(propState => propState.Property == null))
                 {
-                    dynamicProperties.Add(new DynamicPropertyJson() { PropertyName = dynPropState.PropertyName });                    
+                    var dummyProp = new DynamicPropertyJson() { PropertyName = dynPropState.PropertyName };
+
+                    // Preserve ControlPropertyState if it exists
+                    if (dynPropState.ControlPropertyState != null)
+                    {
+                        dummyProp.ControlPropertyState = JsonSerializer.SerializeToElement(dynPropState.ControlPropertyState);
+                    }
+
+                    dynamicProperties.Add(dummyProp);
                 }
 
                 // Reorder to preserve roundtripping
@@ -659,7 +667,7 @@ private static DynamicPropertyJson GetDynamicPropertyEntry(ControlState state, s
         {
             property.Rule = new RuleEntry()
             {
-                InvariantScript = expression,                
+                InvariantScript = expression,
                 RuleProviderType = "Unknown"
             };
         }

src/PAModel/Schemas/adhoc/Control.cs

@@ -23,7 +23,7 @@ public class RuleEntry
         public string RuleProviderType { get; set; } // = "Unknown";
 
         public string Category { get; set; }
-        
+
         [JsonExtensionData]
         public Dictionary<string, JsonElement> ExtensionData { get; set; }
 
@@ -109,7 +109,7 @@ public class DynamicPropertyJson
         public RuleEntry Rule { get; set; }
 
         // object with additional properties
-        public JsonElement ControlPropertyState { get; set; }
+        public JsonElement? ControlPropertyState { get; set; }
 
         [JsonExtensionData]
         public Dictionary<string, object> ExtensionData { get; set; }