feat: improve balance calculations in statistics page and charts with enhanced formatting for large values

components/statistics/monthly-chart.tsx

@@ -37,9 +37,21 @@ export function MonthlyChart({ data, formatCurrency }: MonthlyChartProps) {
               <BarChart data={data}>
                 <CartesianGrid strokeDasharray="3 3" className="stroke-muted" />
                 <XAxis dataKey="month" className="text-xs" />
-                <YAxis className="text-xs" tickFormatter={(v) => `${v}€`} />
+                <YAxis
+                  className="text-xs"
+                  width={80}
+                  tickFormatter={(v) => {
+                    // Format compact pour les grandes valeurs
+                    if (Math.abs(v) >= 1000) {
+                      return `${(v / 1000).toFixed(1)}k€`;
+                    }
+                    return `${Math.round(v)}€`;
+                  }}
+                  tick={{ fill: "var(--muted-foreground)" }}
+                />
                 <Tooltip
                   formatter={(value: number) => formatCurrency(value)}
+                  labelFormatter={(label) => label}
                   contentStyle={{
                     backgroundColor: "var(--card)",
                     border: "1px solid var(--border)",