feat: Add i18n support for AI insights with structured reasoning

Complete i18n implementation for internal service reasoning:
- Update AIInsight interface to include reasoning_data field
- Integrate useReasoningTranslation hook in AI Insights page
- Add translation keys for safety stock, price forecaster, and optimization

Translation coverage (EN/ES/EU):
- Safety Stock: statistical z-score, advanced variability, fixed percentage, errors
- Price Forecaster: price change predictions, volatility alerts, buying recommendations
- Optimization: EOQ calculations, MOQ/max constraints, tier pricing

Benefits:
- AI insights now display in user's preferred language
- Consistent with PO/Batch reasoning translation pattern
- Structured parameters enable rich, contextualized translations
- Falls back gracefully to description field if translation missing

Implementation:
- frontend/src/api/services/aiInsights.ts: Add reasoning_data to interface
- frontend/src/pages/app/analytics/ai-insights/AIInsightsPage.tsx: Translate insights
- frontend/src/locales/*/reasoning.json: Add safetyStock, priceForecaster, optimization keys

This completes the full i18n implementation for the bakery AI system.

frontend/src/api/services/aiInsights.ts

@@ -25,6 +25,11 @@ export interface AIInsight {
   category: 'demand' | 'procurement' | 'inventory' | 'production' | 'sales' | 'system' | 'business';
   title: string;
   description: string;
+  reasoning_data?: {
+    type: string;
+    parameters: Record<string, any>;
+    [key: string]: any;
+  };
   impact_type: 'cost_savings' | 'waste_reduction' | 'yield_improvement' | 'revenue' | 'system_health' | 'process_improvement';
   impact_value?: number;
   impact_unit?: string;

frontend/src/locales/en/reasoning.json

@@ -44,6 +44,29 @@
     "LEAD_TIME_INVALID": "Lead time or demand deviation is zero or negative",
     "NO_DEMAND_DATA": "No historical demand data available (minimum 2 data points required)"
   },
+  "safetyStock": {
+    "statistical_z_score": "Safety stock calculated using statistical method (service level {{service_level}}%, z-score {{z_score}}). Based on demand std dev {{demand_std_dev}} and {{lead_time_days}}-day lead time. Result: {{safety_stock}} units.",
+    "advanced_variability": "Safety stock calculated with advanced variability analysis. Accounts for both demand variability (σ={{demand_std_dev}}) and lead time uncertainty (σ={{lead_time_std_dev}} days). Result: {{safety_stock}} units.",
+    "fixed_percentage": "Safety stock set at {{percentage}}% of {{lead_time_days}}-day demand ({{lead_time_demand}} units). Result: {{safety_stock}} units.",
+    "error_lead_time_invalid": "Cannot calculate safety stock: lead time ({{lead_time_days}} days) or demand std dev ({{demand_std_dev}}) is invalid.",
+    "error_insufficient_data": "Insufficient demand history for safety stock calculation ({{data_points}} data points, need {{min_required}})."
+  },
+  "priceForecaster": {
+    "decrease_expected": "Price expected to decrease {{change_pct}}% over next {{forecast_days}} days. Current: €{{current_price}}, forecast: €{{forecast_mean}}. Recommendation: Wait for better price.",
+    "increase_expected": "Price expected to increase {{change_pct}}% over next {{forecast_days}} days. Current: €{{current_price}}, forecast: €{{forecast_mean}}. Recommendation: Buy now to lock in current price.",
+    "high_volatility": "High price volatility detected (CV={{coefficient}}). Average daily price change: {{avg_daily_change_pct}}%. Recommendation: Wait for price dip.",
+    "below_average": "Current price €{{current_price}} is {{below_avg_pct}}% below historical average (€{{mean_price}}). Favorable buying opportunity.",
+    "stable": "Price is stable. Current: €{{current_price}}, forecast: €{{forecast_mean}} ({{expected_change_pct}}% change expected). Normal procurement timing recommended.",
+    "insufficient_data": "Insufficient price history for reliable forecast ({{history_days}} days available, need {{min_required_days}} days)."
+  },
+  "optimization": {
+    "eoq_base": "Economic Order Quantity calculated: {{eoq}} units (required: {{required_quantity}}, annual demand: {{annual_demand}}). Optimized for {{optimal_quantity}} units.",
+    "moq_applied": "Minimum order quantity constraint applied: {{moq}} units.",
+    "max_applied": "Maximum order quantity constraint applied: {{max_qty}} units.",
+    "no_tiers": "No price tiers available for this product. Base quantity: {{base_quantity}} units at €{{unit_price}} per unit.",
+    "current_tier": "Current pricing tier: €{{current_tier_price}} per unit for {{base_quantity}} units (total: €{{base_cost}}).",
+    "tier_upgraded": "Upgraded to better price tier! Ordering {{tier_min_qty}} units ({{additional_qty}} extra) at €{{tier_price}} per unit saves €{{savings}} compared to {{base_quantity}} units at €{{base_price}}."
+  },
   "jtbd": {
     "health_status": {
       "green": "Everything is running smoothly",

frontend/src/locales/es/reasoning.json

@@ -44,6 +44,29 @@
     "LEAD_TIME_INVALID": "El tiempo de entrega o la desviación de la demanda es cero o negativo",
     "NO_DEMAND_DATA": "No hay datos históricos de demanda disponibles (se requieren mínimo 2 puntos de datos)"
   },
+  "safetyStock": {
+    "statistical_z_score": "Stock de seguridad calculado con método estadístico (nivel de servicio {{service_level}}%, z-score {{z_score}}). Basado en desviación estándar de demanda {{demand_std_dev}} y tiempo de entrega de {{lead_time_days}} días. Resultado: {{safety_stock}} unidades.",
+    "advanced_variability": "Stock de seguridad calculado con análisis avanzado de variabilidad. Considera tanto la variabilidad de demanda (σ={{demand_std_dev}}) como la incertidumbre del tiempo de entrega (σ={{lead_time_std_dev}} días). Resultado: {{safety_stock}} unidades.",
+    "fixed_percentage": "Stock de seguridad establecido en {{percentage}}% de la demanda de {{lead_time_days}} días ({{lead_time_demand}} unidades). Resultado: {{safety_stock}} unidades.",
+    "error_lead_time_invalid": "No se puede calcular el stock de seguridad: el tiempo de entrega ({{lead_time_days}} días) o la desviación estándar de demanda ({{demand_std_dev}}) no son válidos.",
+    "error_insufficient_data": "Historial de demanda insuficiente para calcular stock de seguridad ({{data_points}} puntos de datos, se necesitan {{min_required}})."
+  },
+  "priceForecaster": {
+    "decrease_expected": "Se espera que el precio disminuya {{change_pct}}% en los próximos {{forecast_days}} días. Actual: €{{current_price}}, pronóstico: €{{forecast_mean}}. Recomendación: Esperar mejor precio.",
+    "increase_expected": "Se espera que el precio aumente {{change_pct}}% en los próximos {{forecast_days}} días. Actual: €{{current_price}}, pronóstico: €{{forecast_mean}}. Recomendación: Comprar ahora para asegurar el precio actual.",
+    "high_volatility": "Alta volatilidad de precio detectada (CV={{coefficient}}). Cambio diario promedio de precio: {{avg_daily_change_pct}}%. Recomendación: Esperar caída de precio.",
+    "below_average": "El precio actual €{{current_price}} está {{below_avg_pct}}% por debajo del promedio histórico (€{{mean_price}}). Oportunidad favorable de compra.",
+    "stable": "El precio es estable. Actual: €{{current_price}}, pronóstico: €{{forecast_mean}} (se espera cambio de {{expected_change_pct}}%). Se recomienda tiempo de compra normal.",
+    "insufficient_data": "Historial de precios insuficiente para pronóstico confiable ({{history_days}} días disponibles, se necesitan {{min_required_days}} días)."
+  },
+  "optimization": {
+    "eoq_base": "Cantidad Económica de Pedido calculada: {{eoq}} unidades (requerido: {{required_quantity}}, demanda anual: {{annual_demand}}). Optimizado para {{optimal_quantity}} unidades.",
+    "moq_applied": "Restricción de cantidad mínima de pedido aplicada: {{moq}} unidades.",
+    "max_applied": "Restricción de cantidad máxima de pedido aplicada: {{max_qty}} unidades.",
+    "no_tiers": "No hay niveles de precio disponibles para este producto. Cantidad base: {{base_quantity}} unidades a €{{unit_price}} por unidad.",
+    "current_tier": "Nivel de precio actual: €{{current_tier_price}} por unidad para {{base_quantity}} unidades (total: €{{base_cost}}).",
+    "tier_upgraded": "¡Actualizado a mejor nivel de precio! Pedir {{tier_min_qty}} unidades ({{additional_qty}} extra) a €{{tier_price}} por unidad ahorra €{{savings}} comparado con {{base_quantity}} unidades a €{{base_price}}."
+  },
   "jtbd": {
     "health_status": {
       "green": "Todo funciona correctamente",

frontend/src/locales/eu/reasoning.json

@@ -46,6 +46,29 @@ ko da.",
     "LEAD_TIME_INVALID": "Entrega denbora edo eskaeraren desbideratzea zero edo negatiboa da",
     "NO_DEMAND_DATA": "Ez dago eskaeraren datu historikorik eskuragarri (gutxienez 2 datu puntu behar dira)"
   },
+  "safetyStock": {
+    "statistical_z_score": "Segurtasun-stock kalkulatua metodo estatistikoarekin (zerbitzu-maila {{service_level}}%, z-score {{z_score}}). Eskaeraren desbideratze estandarrean {{demand_std_dev}} eta {{lead_time_days}} eguneko entrega-denboran oinarrituta. Emaitza: {{safety_stock}} unitate.",
+    "advanced_variability": "Segurtasun-stock kalkulatua aldakortasun-analisi aurreratuarekin. Eskaeraren aldakortasuna (σ={{demand_std_dev}}) eta entrega-denboraren ziurgabetasuna (σ={{lead_time_std_dev}} egun) kontuan hartzen ditu. Emaitza: {{safety_stock}} unitate.",
+    "fixed_percentage": "Segurtasun-stock ezarri da {{lead_time_days}} eguneko eskaeraren {{percentage}}%n ({{lead_time_demand}} unitate). Emaitza: {{safety_stock}} unitate.",
+    "error_lead_time_invalid": "Ezin da segurtasun-stock kalkulatu: entrega-denbora ({{lead_time_days}} egun) edo eskaeraren desbideratze estandarra ({{demand_std_dev}}) ez dira baliodunak.",
+    "error_insufficient_data": "Eskaeraren historiala ez da nahikoa segurtasun-stock kalkulatzeko ({{data_points}} datu puntu, {{min_required}} behar dira)."
+  },
+  "priceForecaster": {
+    "decrease_expected": "Espero da prezioa {{change_pct}}% jaitsiko dela hurrengo {{forecast_days}} egunetan. Oraingoa: €{{current_price}}, aurreikuspena: €{{forecast_mean}}. Gomendio: Itxaron prezio hobeago baterako.",
+    "increase_expected": "Espero da prezioa {{change_pct}}% igoko dela hurrengo {{forecast_days}} egunetan. Oraingoa: €{{current_price}}, aurreikuspena: €{{forecast_mean}}. Gomendio: Erosi orain oraingo prezioa ziurtatzeko.",
+    "high_volatility": "Prezio-aldakortasun altua detektatu da (CV={{coefficient}}). Prezioaren eguneko batez besteko aldaketa: {{avg_daily_change_pct}}%. Gomendio: Itxaron prezioaren jaitsierara.",
+    "below_average": "Oraingo prezioa €{{current_price}} batez besteko historikoaren (€{{mean_price}}) {{below_avg_pct}}% azpitik dago. Erosketa-aukera egokia.",
+    "stable": "Prezioa egonkorra da. Oraingoa: €{{current_price}}, aurreikuspena: €{{forecast_mean}} ({{expected_change_pct}}% aldaketa espero da). Ohiko erosketa-denbora gomendatzen da.",
+    "insufficient_data": "Prezioen historiala ez da nahikoa aurreikuspen fidagarrirako ({{history_days}} egun eskuragarri, {{min_required_days}} egun behar dira)."
+  },
+  "optimization": {
+    "eoq_base": "Eskaera Kantitate Ekonomikoa kalkulatu da: {{eoq}} unitate (beharrezkoa: {{required_quantity}}, urteko eskaera: {{annual_demand}}). {{optimal_quantity}} unitatetan optimizatuta.",
+    "moq_applied": "Gutxieneko eskaera-kantitatearen murrizketa aplikatu da: {{moq}} unitate.",
+    "max_applied": "Gehienezko eskaera-kantitatearen murrizketa aplikatu da: {{max_qty}} unitate.",
+    "no_tiers": "Ez dago prezio-mailarik eskuragarri produktu honetarako. Oinarrizko kantitatea: {{base_quantity}} unitate €{{unit_price}} unitateko.",
+    "current_tier": "Oraingo prezio-maila: €{{current_tier_price}} unitateko {{base_quantity}} unitateko (guztira: €{{base_cost}}).",
+    "tier_upgraded": "Prezio-maila hobea lortu da! {{tier_min_qty}} unitate eskatzeak ({{additional_qty}} gehiago) €{{tier_price}} unitateko €{{savings}} aurrezten ditu {{base_quantity}} unitateri €{{base_price}}n konparatuta."
+  },
   "jtbd": {
     "health_status": {
       "green": "Dena ondo dabil",

frontend/src/pages/app/analytics/ai-insights/AIInsightsPage.tsx

@@ -6,12 +6,14 @@ import { useCurrentTenant } from '../../../../stores/tenant.store';
 import { useAuthUser } from '../../../../stores/auth.store';
 import { useAIInsights, useAIInsightStats, useApplyInsight, useDismissInsight } from '../../../../api/hooks/aiInsights';
 import { AIInsight } from '../../../../api/services/aiInsights';
+import { useReasoningTranslation } from '../../../../hooks/useReasoningTranslation';
 
 const AIInsightsPage: React.FC = () => {
   const [selectedCategory, setSelectedCategory] = useState('all');
   const currentTenant = useCurrentTenant();
   const user = useAuthUser();
   const tenantId = currentTenant?.id || user?.tenant_id;
+  const { t } = useReasoningTranslation();
 
   // Fetch real insights from API
   const { data: insightsData, isLoading, refetch } = useAIInsights(
@@ -118,6 +120,32 @@ const AIInsightsPage: React.FC = () => {
     }
   };
 
+  /**
+   * Get translated description for an insight
+   * Uses reasoning_data if available, otherwise falls back to description field
+   */
+  const getInsightDescription = (insight: AIInsight): string => {
+    if (insight.reasoning_data?.type) {
+      // Determine the category prefix based on source
+      let category = 'aiInsights';
+      if (insight.source_model === 'safety_stock_calculator') {
+        category = 'safetyStock';
+      } else if (insight.source_model === 'price_forecaster') {
+        category = 'priceForecaster';
+      } else if (insight.source_model === 'optimization') {
+        category = 'optimization';
+      }
+
+      try {
+        return t(`${category}.${insight.reasoning_data.type}`, insight.reasoning_data.parameters);
+      } catch (e) {
+        // Fall back to description if translation key not found
+        return insight.description;
+      }
+    }
+    return insight.description;
+  };
+
   return (
     <AnalyticsPageLayout
       title="Inteligencia Artificial"
@@ -224,7 +252,7 @@ const AIInsightsPage: React.FC = () => {
                 </div>
                 
                 <h3 className="text-lg font-semibold text-[var(--text-primary)] mb-2">{insight.title}</h3>
-                <p className="text-[var(--text-secondary)] mb-3">{insight.description}</p>
+                <p className="text-[var(--text-secondary)] mb-3">{getInsightDescription(insight)}</p>
                 <p className="text-sm font-medium text-[var(--color-success)] mb-4">{insight.impact}</p>
 
                 {/* Metrics */}