fix: perf damage in data processing by jnp

[bhcao]

See #40 for details.

[CLAassistant]

All committers have signed the CLA.

[chrbrunk]

Hey @bhcao, thanks a lot for this! Looks good to me.

Before, I approve, let me just try to figure out what we can do about the permission issue in the CI.

Also, one small request: could you change the target to develop on mlip. Then we first merge there and then we can on our side update the CHANGELOG and version, before we trigger a new release with the merge to main. Thanks a lot!

[bhcao]

The target has been changed to develop.

[chrbrunk]

Thanks! I think I'll just merge this now as the tests are passing, and the CI permission problem can be solved later on main for future PRs.

I cannot promise that we'll get this merged through to main still today, but that should happen within the next few days at latest.