Three issues in the drift-fix landing (922bddc) addressed:
1. algebra/rotor.py: add rotor_power(R, alpha) — slerp on the rotor manifold
via the rotor's exp/log decomposition. Handles both rotation planes
(cos/sin) and boost planes (cosh/sinh); falls back to identity for
non-simple bivectors or null cases.
2. generate/stream.py: the score-weighted vault recall previously did
`weight*V + (1-weight)*np.eye(V.shape[0])`. Two bugs:
- np.eye produced a 32x32 matrix for a 1D multivector, crashing
versor_apply with a broadcasting error (2 cognition tests failing
on main).
- The linear blend produced multivectors with versor_condition up to
2.2e-2, violating the non-negotiable 1e-6 invariant declared in
CLAUDE.md. Now uses rotor_power(V, weight) which stays on the
manifold by construction (versor_condition <= 1.1e-16).
3. session/context.py: respond() now re-binds result.final_state to
self.state after finalize_turn's anchor pull, restoring the
"respond returns the same object that was vaulted" contract
(test_engine_loop_proof regression).
Verification:
- 41 new tests in tests/test_rotor_power.py covering closure preservation,
alpha=0/1 boundaries, half-angle composition, and word-transition rotors.
- Empirical multi-turn versor_condition stays at machine epsilon with
anchor pull, max 9.4e-7 without (under threshold either way after fix).
- Full suite: 609 passed, 4 skipped, 0 failed.
07f49eb215