add docker swarm support

[darkeagle1337]

Solving the following problem:

#8

[umputun]

couple of critical issues:

1. regex false positives — (.*)\.(\d+)\.(.*) matches any container name with dots and digits, not just swarm containers. names like my.app.v2 get mangled. a tighter pattern like ^(.+)\.(\d+)\.[a-z0-9]{25}$ would match actual swarm task IDs, or the original com.docker.swarm.task.id label approach could be used as primary detection

2. Actor.Attributes ≠ container Labels — activate() passes dockerEvent.Actor.Attributes to buildContainerName, but Actor Attributes don't contain custom container labels like logger.container.name. the label override only works in emitRunningContainers (initial scan), not for live events

3. no tests for buildContainerName/buildGroupName — these have non-trivial regex + label fallback logic that needs coverage

4. scope creep — logger.group.name/logger.container.name labels and APP_UID=995 in Dockerfile are separate features/fixes not related to issue #8. would be better as separate PRs

the overall approach of normalizing swarm names in both code paths is correct though