feat(spo): integrate gestalt bundling, σ-calibration, and truth trajectories

Wire rustynum PRs #74-81 types into ladybug-rs:

- Add rustynum-bnn dependency (CrossPlaneVote, CausalSaliency, HaloType)
- hdr_cascade: MexicanHat::from_sigma_gate() replaces hardcoded thresholds
  with SigmaGate-derived Discovery/Hint bands; AlienSearch::with_sigma_gate()
  and calibrate_from_sigma(); classify_sigma() + significance_to_signal() bridge
- New gestalt module (extensions/spo/gestalt.rs):
  * GestaltState: Crystallizing/Contested/Dissolving/Epiphany from CausalSaliency
  * BundlingProposal: tentative/committed/rejected lifecycle via CollapseGate
  * detect_bundling(): per-plane Hamming analysis → SO/PO/SP halo classification
  * TiltReport + PlaneCalibration: per-axis σ rotation correction
  * TruthTrajectory: temporal audit trail with evidence events
  * CollapseMode: Research/Production/Regulated auto-FLOW thresholds
  * AntialiasedSigma: continuous σ scoring with soft band boundaries

All tests pass. Zero new compilation errors (9 pre-existing in other files).

https://claude.ai/code/session_0152b2NJYnjCJjvMAmgsTx3p

Author: claude

Cargo.toml

@@ -211,6 +211,7 @@ crewai-vendor = { package = "crewai", path = "../crewai-rust" }
 # -----------------------------------------------------------------------------
 rustynum-rs = { path = "../rustynum/rustynum-rs" }
 rustynum-core = { path = "../rustynum/rustynum-core", features = ["avx512"] }
+rustynum-bnn = { path = "../rustynum/rustynum-bnn", features = ["avx512"] }
 rustynum-arrow = { path = "../rustynum/rustynum-arrow", default-features = false, features = ["arrow"] }
 rustynum-holo = { path = "../rustynum/rustynum-holo", features = ["avx512"] }
 rustynum-clam = { path = "../rustynum/rustynum-clam", features = ["avx512"] }