I have not tested this but currently Chunks.java and ChunkSaveCommand.java use Minecraft.getMinecraft().getIntegratedServer(), while this causes no issues while running purely client side there are likely to be crashes or errors on the server side. A better approach to getting the world folder root that works on both sides would be DimensionManager.getCurrentSaveRootDirectory()
I have not tested this but currently Chunks.java and ChunkSaveCommand.java use Minecraft.getMinecraft().getIntegratedServer(), while this causes no issues while running purely client side there are likely to be crashes or errors on the server side. A better approach to getting the world folder root that works on both sides would be DimensionManager.getCurrentSaveRootDirectory()