Refactor expense chart title

Moves the expense chart title outside of the card component for better visual consistency.

src/pages/Analytics.tsx

@@ -1,3 +1,4 @@
+
 import React, { useState } from 'react';
 import NavBar from '@/components/NavBar';
 import ExpenseChart from '@/components/ExpenseChart';
@@ -146,6 +147,7 @@ const Analytics = () => {
         </div>
         
         {/* Category Pie Chart - MOVED DOWN */}
+        <h2 className="text-lg font-semibold mb-3">카테고리별 지출</h2>
         <ExpenseChart data={expenseData} />
         
         {/* Top Spending Categories */}