Resources (assets (css, js, images), lang files, etc) belong to boxes and applications.
Other than their location in the directory structure, Concord has not much to say about them. Following Laravel conventions seems like a good idea though.
module-src/ resources/ |-- assets/ |-- lang/ |-- views/
Feel free to add new directories in the resources folder as per your needs. Concord is a guide not a law ;)
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