Fix examples for deprecated usages

 - Fix Java FunctionCallback chatClient to use toolNames instead of tools to specify the function name
 - Fix MCP FileSystem Application ChatClientBuilder to use defaultToolCallbacks instead of defaultTools

Author: ilayaperumalg

misc/spring-ai-java-function-callback/src/main/java/com/example/java_ai_function_callback/SpringAiJavaFunctionCallbackApplication.java

@@ -26,10 +26,12 @@ public CommandLineRunner init(ChatClient.Builder chatClientBuilder) {
 				ChatClient chatClient = chatClientBuilder.build();
 				ChatResponse response = chatClient
 						.prompt("What are the weather conditions in San Francisco, Tokyo, and Paris? Find the temperature in Celsius for each of the three locations.")
-						.tools("WeatherInfo")
+						.toolNames("WeatherInfo")
 						.call().chatResponse();
 
 				System.out.println("Response: " + response);
+				System.out.println("Exiting successfully");
+				System.exit(0);
 			}
 			catch (Exception e) {
 				System.out.println("Error during weather check: " + e.getMessage());

model-context-protocol/filesystem/src/main/java/org/springframework/ai/mcp/samples/filesystem/Application.java

@@ -29,7 +29,7 @@ public CommandLineRunner predefinedQuestions(ChatClient.Builder chatClientBuilde
 
 		return args -> {
 			var chatClient = chatClientBuilder
-					.defaultTools(new SyncMcpToolCallbackProvider(mcpClient))
+					.defaultToolCallbacks(new SyncMcpToolCallbackProvider(mcpClient))
 					.build();
 
 			System.out.println("Running predefined questions with AI model responses:\n");