algebra/rotor.py and persona/motor.py were calling normalize_to_versor()
which is the gate-only injection primitive. Both are construction-time
sites (building rotors and motors from raw arrays), so the correct call
is unitize_versor().
Also tightens TestINV02 to scan for normalize_to_versor violations only —
unitize_versor has its own legitimate call sites and is not under the
same single-site restriction. Adds a new TestINV02b that verifies
unitize_versor is NOT called inside propagation, generation, or vault
recall paths.
Fixes: INV-02 architectural invariant test failure.
- Add algebra/rotor.py: word_transition_rotor() as a free operator function
- Update algebra/__init__.py: export word_transition_rotor
- Refactor vocab/manifold.py: remove edge_rotor(), add versor grade-norm
invariant check in add() to reject raw coordinate vectors at insertion time
VocabManifold now stores only algebraically valid Cl(4,1) versors and
exposes only relational lookup (CGA inner product). Rotor construction
is a contextual algebra-layer concern, not a vocabulary property.
