Cancellable scripts

[WardBrian]

Currently the analysis/data scripts cannot be cancelled. This is possible to implement in the following way:

• pyodide: similar to sampling, we can destroy and re-create the pyodide worker
• webR: actually supports a .interrupt() function, but this is only available if the SharedArrayBuffer implementation is used, which we currently do not. I believe we would need some extra vercel config: https://vercel.com/guides/fix-shared-array-buffer-not-defined-nextjs-react