[DPE-5109] Split Kraft mode into own service

[zmraul]

Raft mode is now supported via a new service on the snap

• component name: kraft -> /etc/kraft/controller.properties, /var/logs/kraft/
• service name: controller -> snap start charmed-kafka.controller

Notes

${charmed.kafka.log.level} is shared between controller and daemon modes

[deusebio]

I'm wondering if some of the files here are actually needed or they resulted from a copy and paste of some directories. If possible, I would keep the content minimal with respect to what is needed for Kraft

[deusebio]

todo I'm wondering whether the log4j for kraft need to be so similar to the one of Kafka, even featuring some zookeeper references. Also are all appender still relevant? If possible, I would prefer to make this file minimal with respect to the content

[zmraul]

From looking at the kafka examples, both modes (zookeeper and kraft) use the same configuration file, so I just changed references to have ${controller.logs.dir} instead of kafka logs. I can have a closer look at which specific ones are actually used, but the info here is slim

[deusebio]

But they are two different processes, right? If so, honestly, I would not create any additional appender, and just log everything into a single file. We can still keep the charmed.kafka.log.* configuration, but I would make it rather minimal honestly

[deusebio]

question are these beans kraft specific?

[zmraul]

I'm not sure tbh. They are the general ones for the kafka process. I changed the name to follow a controller_[$1_$2] pattern instead of the kafka_[$1_$2] pattern.