feat(customers): add dashboard and customer management

frontend/athena/components/common/DetailSection.tsx

@@ -0,0 +1,19 @@
+import type { ReactNode } from "react";
+
+type Props = {
+  title: string;
+  actions?: ReactNode;
+  children: ReactNode;
+};
+
+export default function DetailSection({ title, actions, children }: Props) {
+  return (
+    <section className="rounded-lg border bg-white p-6">
+      <div className="mb-5 flex items-center justify-between gap-4">
+        <h2 className="text-lg font-semibold text-slate-950">{title}</h2>
+        {actions}
+      </div>
+      {children}
+    </section>
+  );
+}

frontend/athena/components/common/SummaryCard.tsx

@@ -0,0 +1,13 @@
+type Props = {
+  label: string;
+  value: number | string;
+};
+
+export default function SummaryCard({ label, value }: Props) {
+  return (
+    <div className="rounded-lg border bg-white p-5">
+      <p className="text-sm text-slate-500">{label}</p>
+      <p className="mt-2 text-3xl font-semibold text-slate-950">{value}</p>
+    </div>
+  );
+}