Add SendTextMessage to agent component and WebSocket proxy

Sends {"type":"user_message","text":"..."} to the ElevenLabs API.
Agent responds with audio + text exactly as if it heard spoken input.
Useful for testing without a microphone and for text-only NPC interactions.

Available in Blueprint on UElevenLabsConversationalAgentComponent.
Compiles cleanly on UE 5.5 Win64.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Unreal/PS_AI_Agent/Plugins/PS_AI_Agent_ElevenLabs/Source/PS_AI_Agent_ElevenLabs/Private/ElevenLabsConversationalAgentComponent.cpp

@@ -155,6 +155,16 @@ void UElevenLabsConversationalAgentComponent::StopListening()
 	UE_LOG(LogElevenLabsAgent, Log, TEXT("Microphone capture stopped."));
 }
 
+void UElevenLabsConversationalAgentComponent::SendTextMessage(const FString& Text)
+{
+	if (!IsConnected())
+	{
+		UE_LOG(LogElevenLabsAgent, Warning, TEXT("SendTextMessage: not connected. Call StartConversation() first."));
+		return;
+	}
+	WebSocketProxy->SendTextMessage(Text);
+}
+
 void UElevenLabsConversationalAgentComponent::InterruptAgent()
 {
 	if (WebSocketProxy) WebSocketProxy->SendInterrupt();

Unreal/PS_AI_Agent/Plugins/PS_AI_Agent_ElevenLabs/Source/PS_AI_Agent_ElevenLabs/Private/ElevenLabsWebSocketProxy.cpp

@@ -126,6 +126,22 @@ void UElevenLabsWebSocketProxy::SendUserTurnEnd()
 	UE_LOG(LogElevenLabsWS, Log, TEXT("User turn ended (client mode) — stopped sending user_activity."));
 }
 
+void UElevenLabsWebSocketProxy::SendTextMessage(const FString& Text)
+{
+	if (!IsConnected())
+	{
+		UE_LOG(LogElevenLabsWS, Warning, TEXT("SendTextMessage: not connected."));
+		return;
+	}
+	if (Text.IsEmpty()) return;
+
+	// API: { "type": "user_message", "text": "Hello agent" }
+	TSharedPtr<FJsonObject> Msg = MakeShareable(new FJsonObject());
+	Msg->SetStringField(TEXT("type"), ElevenLabsMessageType::UserMessage);
+	Msg->SetStringField(TEXT("text"), Text);
+	SendJsonMessage(Msg);
+}
+
 void UElevenLabsWebSocketProxy::SendInterrupt()
 {
 	if (!IsConnected()) return;

Unreal/PS_AI_Agent/Plugins/PS_AI_Agent_ElevenLabs/Source/PS_AI_Agent_ElevenLabs/Public/ElevenLabsConversationalAgentComponent.h

@@ -135,6 +135,14 @@ public:
 	UFUNCTION(BlueprintCallable, Category = "ElevenLabs")
 	void StopListening();
 
+	/**
+	 * Send a plain text message to the agent without using the microphone.
+	 * The agent will respond with audio and text just as if it heard you speak.
+	 * Useful for testing in the Editor or for text-based interaction.
+	 */
+	UFUNCTION(BlueprintCallable, Category = "ElevenLabs")
+	void SendTextMessage(const FString& Text);
+
 	/** Interrupt the agent's current utterance. */
 	UFUNCTION(BlueprintCallable, Category = "ElevenLabs")
 	void InterruptAgent();

Unreal/PS_AI_Agent/Plugins/PS_AI_Agent_ElevenLabs/Source/PS_AI_Agent_ElevenLabs/Public/ElevenLabsWebSocketProxy.h

@@ -136,6 +136,14 @@ public:
 	UFUNCTION(BlueprintCallable, Category = "ElevenLabs")
 	void SendUserTurnEnd();
 
+	/**
+	 * Send a text message to the agent (no microphone needed).
+	 * Useful for testing or text-only interaction.
+	 * Sends: { "type": "user_message", "text": "..." }
+	 */
+	UFUNCTION(BlueprintCallable, Category = "ElevenLabs")
+	void SendTextMessage(const FString& Text);
+
 	/** Ask the agent to stop the current utterance. */
 	UFUNCTION(BlueprintCallable, Category = "ElevenLabs")
 	void SendInterrupt();