{lyn8578} adding UX for assinging a Python scene builder (#7551)

* {lyn8578} adding UX for assinging a Python scene builder

Signed-off-by: Allen Jackson <23512001+jackalbe@users.noreply.github.com>

* improved the Reset and Assign script logic

Signed-off-by: Allen Jackson <23512001+jackalbe@users.noreply.github.com>

* GUI updates to highlight the scene script


Signed-off-by: Allen Jackson <23512001+jackalbe@users.noreply.github.com>

* save off the script file name instead of holding onto the rule
update the header display name separate from setting the scene

Signed-off-by: Allen Jackson <23512001+jackalbe@users.noreply.github.com>

Code/Editor/Plugins/EditorAssetImporter/AssetImporterWindow.h

@@ -47,6 +47,10 @@ namespace AZ
         {
             class ProcessingOverlayWidget;
         }
+        namespace DataTypes
+        {
+            class IScriptProcessorRule;
+        }
     }
 }
 
@@ -80,6 +84,7 @@ public:
 
 public slots:
     void OnSceneResetRequested();
+    void OnAssignScript();
     void OnOpenDocumentation();
     void OnInspect();
 
@@ -105,6 +110,7 @@ private slots:
     
     void OverlayLayerAdded();
     void OverlayLayerRemoved();
+    void UpdateSceneDisplay(const AZStd::shared_ptr<AZ::SceneAPI::Containers::Scene> scene = {}) const;
 
 private:
     static const AZ::Uuid s_browseTag;
@@ -122,4 +128,6 @@ private:
 
     int m_processingOverlayIndex;
     QSharedPointer<AZ::SceneAPI::SceneUI::ProcessingOverlayWidget> m_processingOverlay;
+
+    AZStd::string m_scriptProcessorRuleFilename;
 };