fix(deps): update rust crate rv to 0.20.0

[renovate-sh-app]

This PR contains the following updates:

Package	Type	Update	Change
rv	dependencies	minor	0.18.0 → 0.20.0

---

Release Notes

promised-ai/rv (rv)

v0.20.1

Compare Source

Fixed

• Occasional overflow issue in StickBreakingDiscrete.
• Some internal StickBreakingDiscrete functions would extend the weights one
  too many times. This would not cause bugs but it's not efficient either.

v0.20.0

Compare Source

Changed

• Added rkyv feature. Supports most distributions.
• DataOrSuffStat is Copy
• DataOrSuffStat is now passed by value to ConjugatePrior methods
• Overhauled experimental stick breaking distribution. Of note:
  • Replaced Arc<RwLock<_>> with ArcSwap-based data structure. Which makes
    the plots of ln_f / seconds as a function of number of cores go up and
    to the right instead of down and to the right. Check
    this video out. If
    you want to see what I mean, port the sbd_bench example over to v0.19.
  • Made the names to modules shorter.
  • Using HalfBeta instead of UnitPowerlLaw because it aligns better with
    how the math in written out.
  • StickBreakingDiscrete now serializes its underlying Rng to maintain
    seed control after a write-read.

v0.19.2

Compare Source

Changed

• Updated lru crate to 0.16.3 in response to RUSTSEC-2026-0002
• Relaxed assertion about appending to CCDF in stick sequence

v0.19.1

Compare Source

Added

• Derive PartialEq for NIX PosteriorParameters

v0.19.0

Compare Source

Added

• Added product distributions expressible via tuples. (Note: Sufficient statistics are locked behind the experimental option since their behavior is not certain.)
• Added ScaledPrior and ShiftedPrior wrappers.

Changed

• Updated to Rust 2024 Edition
• Updated rand, rand_xoshiro, and rand_distr deps.
• Updated nalgebra.
• NormalInvChiSquared, NormalGamma, and NormalInvGamme PpCache for Gaussian conjugate analysis changed. ln_pp_with_cache is much faster.
• Gamma PpCache for Poisson conjugate analysis has been optimized. ln_pp_with_cache is faster.
• Fixed some typos.
• GitHub CI uses nightly since experimental features require nightly rust.
• OnceLock removed on distribution initialization in favor of uniform initialization cost over threads.
• Reworked extract_stat internals.
• CDVM was cleaned up, errors expanded, and parameters made more clear.
• Von Mises were sped up.
• LogSumExp was fixed when encountering -inf.
• NormalInvGamma::ln_pp was sped up.
• NIX PpCache was sped up by 20%.
• NiX Posterior predictive has its speed improved.

---

Configuration

📅 Schedule: (UTC)

• Branch creation
  • At any time (no schedule defined)
• Automerge
  • At any time (no schedule defined)

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

♻ Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

---

• If you want to rebase/retry this PR, check this box

---

Need help?

You can ask for more help in the following Slack channel: #proj-renovate-self-hosted. In that channel you can also find ADR and FAQ docs in the Resources section.