Adjust ExpenseChart label size

Modified the ExpenseChart component to ensure the labels on the pie chart have a consistent text size.

src/components/ExpenseChart.tsx

@@ -27,7 +27,11 @@ const ExpenseChart: React.FC<ExpenseChartProps> = ({ data }) => {
             paddingAngle={5}
             dataKey="value"
             labelLine={false}
-            label={({ name, percent }) => `${name} ${(percent * 100).toFixed(0)}%`}
+            label={({ name, percent }) => (
+              <text className="text-sm" textAnchor="middle" style={{ fontSize: '12px' }}>
+                {`${name} ${(percent * 100).toFixed(0)}%`}
+              </text>
+            )}
           >
             {data.map((entry, index) => (
               <Cell key={`cell-${index}`} fill={entry.color} />