process-usertasks-timer-quarkus: keycloak service expected but missing in docker compose

### Describe the bug

After January '25 changes in docker compose YAML config, keycloak service along with management console were removed. While management console was later added back, keycloak service was not. Keycloak service is now expected by some other services but missing, therefore docker compose doesn't work at all.

### Expected behavior

`docker compose up` starts required containers

### Actual behavior

`docker compose up` doesn't start all required containers

### How to Reproduce?

_No response_

### Output of `uname -a` or `ver`

_No response_

### Output of `java -version`

_No response_

### GraalVM version (if different from Java)

_No response_

### Kogito version or git rev (or at least Quarkus version if you are using Kogito via Quarkus platform BOM)

_No response_

### Build tool (ie. output of `mvnw --version` or `gradlew --version`)

_No response_

### Additional information

_No response_

Start in the process-usertasks-timer-quarkus example and inspect its Docker Compose YAML, comparing the current configuration with the January 2025 changes. Run `docker compose up` to observe the missing service, then verify that the required Keycloak service and management console start with the other containers.

Written by the indexing model from the issue text.