Is the act of an individual collecting money from worshipers in the mosque to make "grave dishes" for the cemetery, and then donating some of them to other cemeteries or to acquaintances, considered an ongoing charity from which people benefit?

The manufacturing of planks used to seal the cracks in a grave where the deceased is placed is a charity for which its doer will be rewarded, but it is not an ongoing charity (sadaqah (definition) jariyah). An ongoing charity is an endowment (waqf) whose principal is preserved and whose benefits are made available. If the donations for manufacturing these planks are designated for a specific village cemetery, it is not permissible to spend them on anything else or to give them as charity without the donors' permission.