Add budget information

Adds "spent amount / target amount" information below the daily, weekly, and monthly tabs.

src/pages/Index.tsx

@@ -99,6 +99,9 @@ const Index = () => {
               </TabsTrigger>
             </TabsList>
             
+            {/* 지출액 / 목표액 라벨 추가 */}
+            <div className="text-sm text-gray-600 mb-2 px-1">지출액 / 목표액</div>
+
             <TabsContent value="daily" className="space-y-4 mt-0">
               <div className="space-y-4">
                 <div>