refactor(core): move app para src e padroniza estrutura

src/app/(dashboard)/accounts/[accountId]/statement/loading.tsx

@@ -0,0 +1,38 @@
+import {
+	AccountStatementCardSkeleton,
+	FilterSkeleton,
+	TransactionsTableSkeleton,
+} from "@/shared/components/skeletons";
+import { Skeleton } from "@/shared/components/ui/skeleton";
+
+/**
+ * Loading state para a página de extrato de conta
+ * Layout: MonthPicker + AccountStatementCard + Filtros + Tabela de lançamentos
+ */
+export default function ExtratoLoading() {
+	return (
+		<main className="flex flex-col gap-6">
+			{/* Month Picker placeholder */}
+			<div className="h-[60px] animate-pulse rounded-2xl bg-foreground/10" />
+
+			{/* Account Statement Card */}
+			<AccountStatementCardSkeleton />
+
+			{/* Seção de lançamentos */}
+			<section className="flex flex-col gap-4">
+				<div className="space-y-6 pt-4">
+					{/* Header */}
+					<div className="flex items-center justify-between">
+						<Skeleton className="h-8 w-48 rounded-2xl bg-foreground/10" />
+					</div>
+
+					{/* Filtros */}
+					<FilterSkeleton />
+
+					{/* Tabela */}
+					<TransactionsTableSkeleton />
+				</div>
+			</section>
+		</main>
+	);
+}