fix(algebra): P11a physics hot paths via algebra.backend (Rust-ready)
Stop wave/Third-Door physics from bypassing native dispatch:
- Route geometric_product / versor_apply / versor_condition / cga_inner
through algebra.backend in wave_manifold, goldtether, trajectory,
dynamic_manifold, surprise, holographic_vault, atlas_packing,
biography, self_authorship.
- Backend: dtype-aware Rust use — f32 workloads use core_rs; f64 wave
residual pins keep Python SOT until f64 GP parity exists. Coerce
arrays for PyO3 bindings; fail soft to Python.
- AST hygiene pin: tests/test_physics_backend_dispatch_hygiene.py
- Docs: RUST.md, runtime_contracts, fidelity (ADR-0235 / UMA hygiene).
Verified: wave + cohesion suites green default and CORE_BACKEND=rust
(with core_rs built). MLX still exploratory off-serve.
44f7258b16