release/0.12.1

[mxfactorial]

0.12.1 (2026-05-22)

added

• GeoCollection::wave_sum — interfering vector sum of a collection (the superposition), the counterpart to total_magnitude; wave_sum().mag <= total_magnitude(), the gap is angular cancellation
• Angle::boost(k) — celestial-sphere (relativistic aberration) boost: scales the stored half-tangent by the Bondi factor k via the grade-keyed Cayley maps, rational, no trig
• Geonum::boost(axis, k) — Lorentz event boost: projection onto the two light-cone nulls (a quarter turn apart) scaled by k and 1/k, interval-preserving, for any boost axis
• chemistry feature: Chemistry extension trait on Geonum deriving the periodic table from blade arithmetic — madelung_order, electron_shell/electron_wave, valence_shell/relativistic_valence_shell, ionization_projection, and the observables ionization_energy (IE1, IE2, successive), electron_affinity, electronegativity; configured by the Lattice enum (Canonical/Custom), validated against NIST
• spacetime_test.rs: metric signature as a π rotation, causal structure (timelike/spacelike/lightlike by grade), Lorentz boosts, the dual as the metric involution (t → −1/t, fixed points the isotropic vectors), the three conics in one half-tangent
• chem_constants_test.rs: the three lattice constants (π/2, π/3, π/4) proven forced as distinct rotation closures, and the 1/n radial law as inv(winding count)

changed

• metric signature test relocated from tensor_test.rs into a dedicated spacetime_test.rs
• chemistry model moved into the chemistry library trait; the chemistry test suites thinned to validate it against NIST