Add (Streaming)ChatClient convinience defaults

Facilitates the creation of multimodal message queries.

spring-ai-core/src/main/java/org/springframework/ai/chat/ChatClient.java

@@ -16,6 +16,10 @@
 package org.springframework.ai.chat;
 
 import org.springframework.ai.chat.prompt.Prompt;
+
+import java.util.Arrays;
+
+import org.springframework.ai.chat.messages.Message;
 import org.springframework.ai.chat.messages.UserMessage;
 import org.springframework.ai.model.ModelClient;
 
@@ -28,6 +32,12 @@ public interface ChatClient extends ModelClient<Prompt, ChatResponse> {
 		return (generation != null) ? generation.getOutput().getContent() : "";
 	}
 
+	default String call(Message... messages) {
+		Prompt prompt = new Prompt(Arrays.asList(messages));
+		Generation generation = call(prompt).getResult();
+		return (generation != null) ? generation.getOutput().getContent() : "";
+	}
+
 	@Override
 	ChatResponse call(Prompt prompt);
 

spring-ai-core/src/main/java/org/springframework/ai/chat/StreamingChatClient.java

@@ -15,8 +15,11 @@
  */
 package org.springframework.ai.chat;
 
+import java.util.Arrays;
+
 import reactor.core.publisher.Flux;
 
+import org.springframework.ai.chat.messages.Message;
 import org.springframework.ai.chat.prompt.Prompt;
 import org.springframework.ai.model.StreamingModelClient;
 
@@ -30,6 +33,13 @@ public interface StreamingChatClient extends StreamingModelClient<Prompt, ChatRe
 						: response.getResult().getOutput().getContent());
 	}
 
+	default Flux<String> call(Message... messages) {
+		Prompt prompt = new Prompt(Arrays.asList(messages));
+		return stream(prompt).map(response -> (response.getResult() == null || response.getResult().getOutput() == null
+				|| response.getResult().getOutput().getContent() == null) ? ""
+						: response.getResult().getOutput().getContent());
+	}
+
 	@Override
 	Flux<ChatResponse> stream(Prompt prompt);
 

spring-ai-core/src/main/java/org/springframework/ai/chat/messages/UserMessage.java

@@ -15,6 +15,7 @@
  */
 package org.springframework.ai.chat.messages;
 
+import java.util.Arrays;
 import java.util.List;
 
 import org.springframework.core.io.Resource;
@@ -38,6 +39,10 @@ public class UserMessage extends AbstractMessage {
 		super(MessageType.USER, textContent, mediaList);
 	}
 
+	public UserMessage(String textContent, Media... media) {
+		this(textContent, Arrays.asList(media));
+	}
+
 	@Override
 	public String toString() {
 		return "UserMessage{" + "content='" + getContent() + '\'' + ", properties=" + properties + ", messageType="