feat(default): add real rankings data

web/default/src/features/rankings/api.ts

@@ -0,0 +1,15 @@
+import { api } from '@/lib/api'
+import type { RankingPeriod, RankingsSnapshot } from './types'
+
+type RankingsResponse = {
+  success: boolean
+  message?: string
+  data: RankingsSnapshot
+}
+
+export async function getRankings(
+  period: RankingPeriod
+): Promise<RankingsResponse> {
+  const res = await api.get('/api/rankings', { params: { period } })
+  return res.data
+}