feat: Phase 4 — Moteur Probabiliste & Apprentissage Automatique

Sprint 4.1 — Bayesian Updating
- database.py: update_bayesian_posteriors() — Beta(α,β) posteriors sur trades matures
- database.py: get_bayesian_posteriors() — posteriors + IC 95% + dérive prior GPT vs posterior
- Colonnes Bayésiennes ajoutées : bayesian_alpha, bayesian_beta, bayesian_win_rate, bayesian_sample_size
- auto_cycle.py: appel update_bayesian_posteriors() en Step 5.5 (après scoring)

Sprint 4.2 — Détection Automatique de Régimes (K-Means numpy pur)
- database.py: detect_and_save_regime_clusters() — K-Means sur 7 gauges macro (VIX, slope, DXY…)
- database.py: get_regime_cluster_history() — timeline des clusters
- database.py: get_regime_transition_matrix() — P(cluster j | cluster i) sur N transitions
- Table regime_clusters avec anomaly_flag (points > 3σ)
- auto_cycle.py: appel detect_and_save_regime_clusters() en Step 5.6

Sprint 4.3 — Embeddings Sémantiques (remplace Jaccard)
- database.py: get_or_create_pattern_embedding() — OpenAI text-embedding-3-small, stocké en DB
- database.py: max_cosine_similarity_vs_existing() — similarité cosinus vs patterns existants
- Table pattern_embeddings avec vecteur JSON + model_version
- auto_cycle.py: _is_duplicate_pattern() — cosinus seuil 0.75 avec fallback Jaccard automatique

Sprint 4.4 — Tableau de Bord Analytique Avancé
- AnalyticsAdvanced.tsx: nouvelle page /analytics-advanced
  • BayesianTable : prior GPT vs WR bayésien ± IC 95%, dérive, niveau de confiance
  • ClusterTimeline : timeline colorée des clusters + anomalies
  • TransitionMatrix : heatmap P(j|i) avec diagonale auto-transition
  • EmbeddingsSummary : liste des patterns vectorisés
  • Boutons "Bayesian update" et "Détecter régime" avec mutation React Query
- analytics.py router : 5 nouveaux endpoints (bayesian, regime-clusters, transitions, detect, embeddings)
- useApi.ts : 4 nouveaux hooks (useBayesianPosteriors, useRegimeClusters, useRegimeTransitions, usePatternEmbeddings)
- App.tsx + Sidebar.tsx : route /analytics-advanced + entrée menu

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/src/components/layout/Sidebar.tsx

@@ -1,7 +1,7 @@
 import { NavLink } from 'react-router-dom'
 import {
   LayoutDashboard, Globe, BarChart2, FlaskConical,
-  History, Calendar, TrendingUp, Zap, DollarSign, Settings, BrainCircuit, Activity, BookOpen, FileBarChart, Brain, ShieldAlert
+  History, Calendar, TrendingUp, Zap, DollarSign, Settings, BrainCircuit, Activity, BookOpen, FileBarChart, Brain, ShieldAlert, Microscope
 } from 'lucide-react'
 import { useGeoRiskScore, useAiStatus, usePortfolioSummary } from '../../hooks/useApi'
 import clsx from 'clsx'
@@ -18,6 +18,7 @@ const nav = [
   { to: '/rapport', icon: FileBarChart, label: 'Rapport IA' },
   { to: '/super-contexte', icon: Brain, label: 'Super Contexte' },
   { to: '/analytics', icon: FlaskConical, label: 'Analytics' },
+  { to: '/analytics-advanced', icon: Microscope, label: 'Analytics Avancées' },
   { to: '/risk', icon: ShieldAlert, label: 'Risk Dashboard' },
   { to: '/backtest', icon: History, label: 'Backtest' },
   { to: '/calendar', icon: Calendar, label: 'Calendrier' },