add loading state and auth back

[ReynardoEW]

DefiLlama/defillama-server#10489 < need this first pr before is broken due to cors problem

[mintdart]

most csv downloads are instant as the data is already there on pai ge which we use for charts, tables etc , so no need of a loading indicator for those buttons

i changed the CsvDownloadButton component to accept prepareCsv function or onClick & isLoading

if the csv depends on an external api , we need to use onClick & isLoading props

if not use prepareCsv prop