scripting: drop ManualConfigurationLoading and kotlin.gradle.scripts.useIdeaProjectImport registry flag

idea/idea-core/src/org/jetbrains/kotlin/idea/core/script/configuration/DefaultScriptingSupport.kt

@@ -396,7 +396,7 @@ abstract class DefaultScriptingSupportBase(val manager: CompositeScriptConfigura
         getAppliedConfiguration(file.originalFile.virtualFile) != null
 
     fun isConfigurationLoadingInProgress(file: KtFile): Boolean {
-        return !hasCachedConfiguration(file) && !ScriptConfigurationManager.isManualConfigurationLoading(file.originalFile.virtualFile)
+        return !hasCachedConfiguration(file)
     }
 
     fun getOrLoadConfiguration(

idea/idea-core/src/org/jetbrains/kotlin/idea/core/script/configuration/listener/ScriptChangesNotifier.kt

@@ -91,8 +91,6 @@ internal class ScriptChangesNotifier(
     private fun getListener(project: Project, file: VirtualFile): ScriptChangeListener? {
         if (project.isDisposed || areListenersDisabled()) return null
 
-        if (ScriptConfigurationManager.isManualConfigurationLoading(file)) return null
-
         return listeners.firstOrNull { it.isApplicable(file) }
     }
 

idea/idea-core/src/org/jetbrains/kotlin/idea/core/script/configuration/loader/DefaultScriptConfigurationLoader.kt

@@ -40,8 +40,6 @@ open class DefaultScriptConfigurationLoader(val project: Project) : ScriptConfig
     ): Boolean {
         val virtualFile = ktFile.originalFile.virtualFile
 
-        if (ScriptConfigurationManager.isManualConfigurationLoading(virtualFile)) return false
-
         val result = getConfigurationThroughScriptingApi(ktFile, virtualFile, scriptDefinition)
 
         if (KotlinScriptingSettings.getInstance(project).autoReloadConfigurations(scriptDefinition)) {