You don't need the map_each here, files are documented to stringify to their mapped exec paths.

Hmm, not sure that's true. Path mapping automatically only applies when it doesn't cause collisions within an action. Is the layout in the zip based on the literal config prefixes in the path? Then I could see this problematic, but that would be pretty unreliable even without path mapping.

You don't need add_all or map_each here, just plain add and format. Using nested args with use_param_file could be even better.