Currently both API and GenServer callbacks are defined under the single GSS.Spreadsheet module.
We should leave API layer in GSS.Spreadsheet and transfer callbacks into a separate GSS.Spreadsheet.Server module.
Update the related supervisors, limiters, tests (all tests should pass).
Currently both API and GenServer callbacks are defined under the single GSS.Spreadsheet module.
We should leave API layer in
GSS.Spreadsheetand transfer callbacks into a separateGSS.Spreadsheet.Servermodule.Update the related supervisors, limiters, tests (all tests should pass).