In standalone mode StandardLogger calls setLevel(logging.DEBUG)
unconditionally, so neither the ULTIMATE_DEBUG environment variable nor
debug_mode in config.json has any effect and every deployment logs at DEBUG.
That is a lot of noise for a service that otherwise runs unattended, and it
makes the real warnings hard to find in the container log.
Resolve the level instead: ULTIMATE_DEBUG first, then debug_mode, defaulting
to INFO. The Kodi-addon path is untouched, since Kodi controls the level there.