The upload coordinator reads the mount id from the driver config to drop
postprocessing results that belong to another storage. The dataprovider
does not add it to the driver config the way the storageprovider does,
so without it the coordinator accepts every result for posix.
Assisted-by: Claude Code:claude-opus-5-5
Signed-off-by: Jörn Friedrich Dreyer <jfd@butonic.de>