Add ackMode attribute to @KafkaListener annotation

This commit introduces a new ackMode attribute to the @KafkaListener
annotation, enabling per-listener acknowledgment mode configuration.
This allows developers to override the container factory's default
ackMode on a per-listener basis.

The ackMode attribute accepts string values corresponding to
ContainerProperties.AckMode enum values (e.g., "RECORD", "BATCH",
"MANUAL", "MANUAL_IMMEDIATE").

Signed-off-by: Go BeomJun <alap_u@naver.com>

Author: K-jun98

spring-kafka/src/main/java/org/springframework/kafka/annotation/KafkaListener.java

@@ -344,7 +344,7 @@
 	 * <p>
 	 * Supports SpEL {@code #{...}} and property placeholders {@code ${...}}.
 	 * @return the ack mode (case-insensitive), or empty string to use factory default.
-	 * @since 4.1
+	 * @since 4.0.1
 	 * @see org.springframework.kafka.listener.ContainerProperties.AckMode
 	 */
 	String ackMode() default "";