feat(pillar): add Pillars 12-14 (implemented) and update mod.rs

Substrate-tier pillars native to ndarray:
- Pillar 12: Splat-construction rotation invariance.
  4096 synthetic (scale, quat) pairs; certifies Σ = R·diag(s²)·Rᵀ is SPD
  and trace/det/Frobenius rotation invariants hold within f32 precision.
- Pillar 13: HHTL cascade contraction.
  256 cascades × depth 4 at lr=0.5; certifies almost-sure d_t ≤ d_{t-1}
  AND per-level mean ratio = (1-lr) within CLT tolerance σ/√N_CASCADES.
- Pillar 14: OGIT type-gate lattice closure.
  64 synthetic DAG schemas × 64 types; certifies reflexivity +
  antisymmetry + transitivity after Floyd-Warshall closure.

mod.rs registers pillars 12-17 alongside migrated 6-11, exposes
run_substrate_tier() convenience runner, and adds tier-documenting
module docs. All pillars share existing prove_runner.rs harness.

Author: claude