debug: true does not make the indexing logs visible in docker logs

Describe the Bug

With debug: true set in the config, docker logs still shows almost nothing about indexing. The detail is produced — it goes to persistent_storage/logs/ccb.log — but the stream a container deployment is actually read from stays nearly silent, because the stderr handler is pinned at WARNING:

# logger_config.yaml
handlers:
  stderr:
    class: logging.StreamHandler
    level: WARNING
    ...
  file_json:
    class: logging.handlers.RotatingFileHandler
    level: DEBUG
    filename: logs/ccb.log

logger_config.k8s.yaml has the stderr handler at DEBUG, so the k8s deployment does not have this problem — only the manual-install and Docker paths do.

Why it matters

Everything that describes what indexing is doing is at INFO or DEBUG:

• Using N parallel file parsing workers
• Dispatching N file chunk(s)
• Waiting for file chunk 1/8 future to complete
• embed_sources finished for 4 source(s): 3 succeeded, 1 errored and the per-source error dict
• No documents to index

None of it reaches docker logs. What does reach it is the ERROR from a failed queue fetch, so the visible log is a stream of tracebacks with no surrounding context.

The practical consequence is that a healthy-but-slow run and a genuinely stuck one look identical from outside the container. We spent a long time treating the silence as evidence that the indexing thread had died — it had not; it was working and simply not saying so where we were looking. The information that eventually resolved it was in ccb.log the whole time.

Suggested fix

Have debug: true also lower the stderr handler, so turning debug on makes the logs visible where they are read. PR follows.

Two smaller things noticed nearby

• context_chat_backend/network_em.py:24 uses logging.getLogger('ccb.nextwork_em') — looks like a typo for network_em.
• _setup_log_levels() in main.py lists the ccb.* loggers explicitly but omits ccb.task_fetcher and ccb.nextwork_em. It is harmless today, since they inherit DEBUG from the ccb parent configured in the YAML, but the list reads as if it were exhaustive.

Setup Details

Nextcloud version: 34.0.3
context_chat / context_chat_backend: 5.4.0 / 5.4.1
Deployment: manual-install deploy daemon, Docker, four backend instances

Start with logger_config.yaml and the debug handling in main.py, then compare logger_config.k8s.yaml to see how the stderr handler is configured. Verify that enabling debug makes indexing messages visible through docker logs while preserving the existing file logging, and run the relevant project tests or a Docker indexing run to confirm the output.