[kotlin] Drop beta status for K2 mode

#KTIJ-31560 Fixed

GitOrigin-RevId: 3301d629dceb26ed4d4b6b678e720e4ad488281b

plugins/kotlin/base/plugin/resources/messages/KotlinBasePluginBundle.properties

@@ -17,7 +17,7 @@ kotlin.dist.downloading.failed=Kotlin dist downloading failed
 configuration.feature.text.new.java.to.kotlin.converter=New Java to Kotlin Converter
 
 kotlin.plugin.kind.k1=K1 mode
-kotlin.plugin.kind.k2=K2 mode (Beta)
+kotlin.plugin.kind.k2=K2 mode
 kotlin.plugin.kind.text=Kotlin plugin: {0}
 
 kotlin.analyzer.version.0=Kotlin analyzer version: {0}

plugins/kotlin/onboarding/resources/messages/FeedbackBundle.properties

@@ -57,4 +57,4 @@ action.org.jetbrains.kotlin.onboarding.gradle.ShowBuildProcessSatisfactionDialog
 enable.k2=Enable K2
 enable.k2.mode=Enable K2 Mode
 enable.action.name=Enable
-enable.k2.mode.notification.text=It looks like you are using Kotlin 2.0. The new K2 mode (Beta) brings performance and stability improvements. Would you like to enable it?
+enable.k2.mode.notification.text=It looks like you are using Kotlin 2.0. The new K2 mode brings performance and stability improvements. Would you like to enable it?

plugins/kotlin/preferences/src/org/jetbrains/kotlin/idea/configuration/ui/KotlinPluginKindSwitcherController.kt

@@ -96,7 +96,6 @@ class KotlinPluginKindSwitcherController {
                 }.onChanged {
                     chosenKind = KotlinPluginMode.of(it.isSelected)
                 }.gap(RightGap.SMALL)
-                icon(AllIcons.General.Beta).align(AlignY.BOTTOM)
                 updateCheckBoxToChosenKind()
                 if (canSwitchKotlinPluginModeViaUI()) {
                     comment(KotlinPreferencesBundle.message("kotlin.plugin.type.restart.required.comment"))