v0.1.0-alpha.1

First public pre-release.

Rust N-body workspace with a federated perturbation-operator architecture: core library (IAS15, WHFast, Mercurius, implicit midpoint), operator crates (apsis-1pn, apsis-radiation, apsis-central), Python bindings, a REBOUND cross-implementation parity portfolio, and CI-gated validation (Mercury 1PN error budget, cross-platform bit-reproducibility). Paper draft and lab notebooks are in-tree; see README for scope and status.

An earlier private-era checkpoint carried this tag (2026-05-02); its tree is preserved at checkpoint-2026-05-02.