Add redis: Boot 4.1 + Spring Data Redis 4.1, the JDK-serialisation default vs Jackson 3 serializers, @RedisHash TTL and keyspace events, @RedisListener, and Redis as the Spring cache

Co-Authored-By: Claude Sonnet 5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01B38FGKKam5SCGgwgduVAh3

redis/docs/output/06-jackson-serializers.txt

@@ -0,0 +1,30 @@
+# Jackson 3 serializers: JacksonJsonRedisSerializer and GenericJacksonJsonRedisSerializer
+
+
+--- JacksonJsonRedisSerializer<User>: one type, plain JSON ---
+value serializer: org.springframework.data.redis.serializer.JacksonJsonRedisSerializer
+userTemplate.opsForValue().set("user:1", new User(1, "Ankur"))
+$ redis-cli -p 6390 KEYS '*'
+user:1
+$ redis-cli -p 6390 GET user:1
+{"id":1,"name":"Ankur"}
+read back: User[id=1, name=Ankur] (User)
+
+--- GenericJacksonJsonRedisSerializer with an allow-list: any type, plus @class ---
+value serializer: org.springframework.data.redis.serializer.GenericJacksonJsonRedisSerializer
+jsonTemplate.opsForValue().set("user:2", new User(2, "Ankur"))
+$ redis-cli -p 6390 GET user:2
+{"@class":"com.ankurm.redis.model.User","id":2,"name":"Ankur"}
+read back: User[id=2, name=Ankur] (User)
+
+--- GenericJacksonJsonRedisSerializer with no typing configured ---
+plain.opsForValue().set("user:3", new User(3, "Ankur"))
+$ redis-cli -p 6390 GET user:3
+{"id":3,"name":"Ankur"}
+read back: {id=3, name=Ankur} (LinkedHashMap)
+
+--- Two different shapes of the same JSON ---
+$ redis-cli -p 6390 GET user:1
+{"id":1,"name":"Ankur"}
+$ redis-cli -p 6390 GET user:2
+{"@class":"com.ankurm.redis.model.User","id":2,"name":"Ankur"}