perf(admin): optimize large-dataset loading for dashboard/users/accounts/ops

backend/internal/handler/admin/account_today_stats_cache.go

@@ -0,0 +1,46 @@
+package admin
+
+import (
+	"sort"
+	"strconv"
+	"strings"
+	"time"
+)
+
+var accountTodayStatsBatchCache = newSnapshotCache(30 * time.Second)
+
+func normalizeAccountIDList(accountIDs []int64) []int64 {
+	if len(accountIDs) == 0 {
+		return nil
+	}
+	seen := make(map[int64]struct{}, len(accountIDs))
+	out := make([]int64, 0, len(accountIDs))
+	for _, id := range accountIDs {
+		if id <= 0 {
+			continue
+		}
+		if _, ok := seen[id]; ok {
+			continue
+		}
+		seen[id] = struct{}{}
+		out = append(out, id)
+	}
+	sort.Slice(out, func(i, j int) bool { return out[i] < out[j] })
+	return out
+}
+
+func buildAccountTodayStatsBatchCacheKey(accountIDs []int64) string {
+	if len(accountIDs) == 0 {
+		return "accounts_today_stats_empty"
+	}
+	var b strings.Builder
+	b.Grow(len(accountIDs) * 6)
+	b.WriteString("accounts_today_stats:")
+	for i, id := range accountIDs {
+		if i > 0 {
+			b.WriteByte(',')
+		}
+		b.WriteString(strconv.FormatInt(id, 10))
+	}
+	return b.String()
+}