Based on commit 1dbe4db
- Split into two crates, lib and cli
- upgrade stwo, marked one stwo test `should_panic` @ShuangWu121
- various clippy and fmt fixes linked to the rust version update
- bring all rust versions to 2025-05-14. CI still installs other
versions for openvm which uses them internally. The stable rust version
we test on is bumped to 1.85
- remove `examples` and related tests, which test the powdr crate on the
previous version of powdr (since it uses another nightly). Happy to
discuss this if it's important @leonardoalt