IJPL-164254 Create an API to get terminal models right after terminal initialization

It is needed to integrate AI features implicitly.

IJ-CR-148020

(cherry picked from commit 0a66057c324509fd7bf9013c7e0b025f6243649d)

GitOrigin-RevId: 4d3265284cd045bfc78ce52f3265b04b9d34b5f4

plugins/terminal/src/org/jetbrains/plugins/terminal/block/BlockTerminalInitializationListener.kt

@@ -0,0 +1,17 @@
+// Copyright 2000-2024 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
+package org.jetbrains.plugins.terminal.block
+
+import com.intellij.util.messages.Topic
+import org.jetbrains.annotations.ApiStatus
+import org.jetbrains.plugins.terminal.block.output.TerminalOutputModel
+import org.jetbrains.plugins.terminal.block.prompt.TerminalPromptModel
+
+@ApiStatus.Internal
+interface BlockTerminalInitializationListener {
+  fun modelsInitialized(promptModel: TerminalPromptModel, outputModel: TerminalOutputModel)
+
+  companion object {
+    @Topic.ProjectLevel
+    val TOPIC: Topic<BlockTerminalInitializationListener> = Topic(BlockTerminalInitializationListener::class.java, Topic.BroadcastDirection.NONE)
+  }
+}

plugins/terminal/src/org/jetbrains/plugins/terminal/block/TerminalWidgetImpl.kt

@@ -67,6 +67,10 @@ internal class TerminalWidgetImpl(
       Disposer.register(this, session)
       BlockTerminalView(project, session, settings, terminalTitle).also {
         installStartupResponsivenessReporter(project, checkNotNull(options.startupMoment), session)
+        project.messageBus.syncPublisher(BlockTerminalInitializationListener.TOPIC).modelsInitialized(
+          it.promptView.controller.model,
+          it.outputView.controller.outputModel
+        )
       }
     }
     else {