Setup weekly benchmark run for precise results

[smarr]

For better performance tracking, we need a more reliable but resource intensive performance tracking setup.

Results should be almost paper ready, i.e. include enough warmup. It should all be on the somns-speed for easy access.

• [ ] AWFY vs. Java
• [ ] Savina vs. Scala
• [ ] full batch of language feature microbenchmarks

Ideally, it only is triggered if there are new commits in the repo.