1.4.1 (build 42): contribución por snapshot, fixes Period vs Period y navegación iPad

- 151: contribución editable por snapshot en cualquier modo (quitado gate detailed)
  con diálogo de propagación al editar: solo este / adelante / atrás / todos
  (SnapshotRepository.propagateContribution, SnapshotFormViewModel.contributionChanged)
- 148: Period vs Period mostraba mal el último mes del period B — la agrupación usaba
  chartMonth(for:) que aplicaba el grace-period del check-in a snapshots históricos;
  ahora agrupa por mes calendario crudo
- 152: iPad Sources no saltaba entre fuentes — añadido .id() al SourceDetailView para
  recrear el StateObject al cambiar de selección
- 146/147: Year vs Year con forecast del año en curso (asterisco de estimado) y KPIs
  arriba / detalle debajo
- 145: card de contribución mensual en SourceDetailView
- Nuevas claves snapshot_contribution_propagate_* en los 7 idiomas

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_015qUZrBusG82T37R7PeokqJ

PortfolioJournal/Views/Charts/PredictionChartView.swift

@@ -77,6 +77,28 @@ struct PredictionChartView: View {
                         .symbolSize(24)
                     }
 
+                    // Bull scenario line (upper confidence interval)
+                    ForEach(predictions) { prediction in
+                        LineMark(
+                            x: .value("Date", prediction.date),
+                            y: .value("Bull", NSDecimalNumber(decimal: prediction.confidenceInterval.upper).doubleValue),
+                            series: .value("Scenario", "bull")
+                        )
+                        .foregroundStyle(Color.positiveGreen.opacity(0.7))
+                        .lineStyle(StrokeStyle(lineWidth: 1.5, dash: [4, 3]))
+                    }
+
+                    // Bear scenario line (lower confidence interval)
+                    ForEach(predictions) { prediction in
+                        LineMark(
+                            x: .value("Date", prediction.date),
+                            y: .value("Bear", NSDecimalNumber(decimal: prediction.confidenceInterval.lower).doubleValue),
+                            series: .value("Scenario", "bear")
+                        )
+                        .foregroundStyle(Color.negativeRed.opacity(0.7))
+                        .lineStyle(StrokeStyle(lineWidth: 1.5, dash: [4, 3]))
+                    }
+
                     // Connect historical to prediction
                     if let lastHistorical = historicalData.last,
                        let firstPrediction = predictions.first {
@@ -114,6 +136,17 @@ struct PredictionChartView: View {
                 }
                 .frame(height: 280)
 
+                // Stats row
+                if let currentValue = historicalData.last?.value,
+                   let lastPred = predictions.last {
+                    ChartStatsRow(stats: [
+                        ChartStat(label: "Current", value: currentValue.compactCurrencyString, color: .appPrimary),
+                        ChartStat(label: "Base (\(predictions.count)M)", value: lastPred.predictedValue.compactCurrencyString, color: .appSecondary),
+                        ChartStat(label: "Bull case", value: lastPred.confidenceInterval.upper.compactCurrencyString, color: .positiveGreen),
+                        ChartStat(label: "Bear case", value: lastPred.confidenceInterval.lower.compactCurrencyString, color: .negativeRed),
+                    ])
+                }
+
                 // Legend
                 HStack(spacing: 20) {
                     HStack(spacing: 6) {
@@ -150,6 +183,24 @@ struct PredictionChartView: View {
                             .font(.caption)
                             .foregroundColor(.secondary)
                     }
+
+                    HStack(spacing: 6) {
+                        Rectangle()
+                            .fill(Color.positiveGreen.opacity(0.7))
+                            .frame(width: 20, height: 2)
+                        Text("Bull")
+                            .font(.caption)
+                            .foregroundColor(.secondary)
+                    }
+
+                    HStack(spacing: 6) {
+                        Rectangle()
+                            .fill(Color.negativeRed.opacity(0.7))
+                            .frame(width: 20, height: 2)
+                        Text("Bear")
+                            .font(.caption)
+                            .foregroundColor(.secondary)
+                    }
                 }
 
                 // Prediction details
@@ -195,6 +246,14 @@ struct PredictionChartView: View {
                             }
                         }
                     }
+
+                    Divider().padding(.vertical, 4)
+                    ChartDataTable(
+                        rows: predictionTableRows,
+                        valueHeader: "Base",
+                        deltaPrevHeader: "Bull",
+                        deltaFirstHeader: "Bear"
+                    )
                 }
             } else {
                 VStack(spacing: 12) {
@@ -220,6 +279,19 @@ struct PredictionChartView: View {
         .cornerRadius(AppConstants.UI.cornerRadius)
         .shadow(color: .black.opacity(0.05), radius: 8, y: 2)
     }
+
+    private var predictionTableRows: [ChartDataTableRow] {
+        predictions.map { pred in
+            ChartDataTableRow(
+                label: chartTableDateLabel(pred.date),
+                value: pred.predictedValue.compactCurrencyString,
+                deltaPrev: pred.confidenceInterval.upper.compactCurrencyString,
+                deltaFirst: pred.confidenceInterval.lower.compactCurrencyString,
+                isPrevPositive: true,
+                isFirstPositive: false
+            )
+        }
+    }
 }
 
 #Preview {