[ULC] Add compiler flag -Xdisable-ultra-light-classes to fallback to light implementation in CLI

idea/idea-analysis/src/org/jetbrains/kotlin/idea/caches/resolve/IDELightClassGenerationSupport.kt

@@ -7,6 +7,7 @@ package org.jetbrains.kotlin.idea.caches.resolve
 
 import com.intellij.openapi.module.ModuleUtilCore
 import com.intellij.openapi.project.Project
+import com.intellij.openapi.util.registry.Registry
 import com.intellij.psi.search.GlobalSearchScope
 import com.intellij.psi.util.CachedValueProvider
 import com.intellij.psi.util.CachedValuesManager
@@ -89,6 +90,10 @@ class IDELightClassGenerationSupport(project: Project) : LightClassGenerationSup
 
     override fun getUltraLightClassSupport(element: KtElement): KtUltraLightSupport = KtUltraLightSupportImpl(element)
 
+    override val useUltraLightClasses: Boolean
+        get() =
+            !KtUltraLightSupport.forceUsingOldLightClasses && Registry.`is`("kotlin.use.ultra.light.classes", true)
+
     private val scopeFileComparator = JavaElementFinder.byClasspathComparator(GlobalSearchScope.allScope(project))
 
     override fun createDataHolderForClass(classOrObject: KtClassOrObject, builder: LightClassBuilder): LightClassDataHolder.ForClass {