Concatenate message header and content, parse message content

[tohkoecalo (Alex)]

I setup filebeat to send logs to elasticsearch but for now I have two problems.
First, I receive my message header and content in two separate records. In Kibana interface they are shown like this:

But in source file this is one record:

The second problem is, that I want to parse message content and get its separate parts in different columns in Kibana. I tried to do it with dissect processor, but no fields are present in message details. My filebeat config yml file:

filebeat.config:
  modules:
    path: ${path.config}/modules.d/*.yml
    reload.enabled: false

filebeat.inputs:
- type: log
  paths:
    - /usr/share/filebeat/logs/app.log
  pattern: '^[[:space:]]'
  negate: false
  match: after

processors:
  - add_host_metadata: ~
  - dissect:
      tokenizer: '%{@timestamp} [%{service.pid}] %{log.logger} [%{service.thread_id}] [%{log.level}] %{message}'
      field: "message"
      target_prefix: ""
  - timestamp:
      field: "@timestamp"
      layouts:
        - '2006-01-02T15:04:05,999'
      test:
        - '2024-05-23T14:57:14,818'

output.elasticsearch:
  hosts: '${ELASTICSEARCH_HOSTS:127.0.0.1:9200}'
  username: '${ELASTICSEARCH_USERNAME:elastic}'
  password: '${ELASTICSEARCH_PASSWORD:elastic}'

And the message details are:

Can I parse my message with filebeat itself or I need to use Grok? Can I also show my message header and content as a single record?