Add stress, precision support, compute

[anjohan]

Update main to remove the mess of stress/multicut/compute.

This includes:

• Adding precision support (default is 3264).
• Add support for cutoff matrix.
• Add padding by 5% to the Kokkos version for more consistent performance, see fig. 5 of bio paper.
• Adding stress support. Requires models to be built with StressForceOutput.
• Adding the compute for custom output, both global and per-atom. Documented in README.

Unfortunately, linting happened for pair_allegro.cpp. I don't like the end result, but oh well.