feat(ops): 运维界面展示 Antigravity 账号 scope 级别限流统计

在运维监控的并发/排队卡片中，为 Antigravity 平台账号显示各 scope
(claude/gemini_text/gemini_image) 的限流数量统计，便于管理员了解
哪些 scope 正在被限流。

backend/internal/service/ops_account_availability.go

@@ -67,6 +67,8 @@ func (s *OpsService) GetAccountAvailabilityStats(ctx context.Context, platformFi
 
 		isAvailable := acc.Status == StatusActive && acc.Schedulable && !isRateLimited && !isOverloaded && !isTempUnsched
 
+		scopeRateLimits := acc.GetAntigravityScopeRateLimits()
+
 		if acc.Platform != "" {
 			if _, ok := platform[acc.Platform]; !ok {
 				platform[acc.Platform] = &PlatformAvailability{
@@ -84,6 +86,14 @@ func (s *OpsService) GetAccountAvailabilityStats(ctx context.Context, platformFi
 			if hasError {
 				p.ErrorCount++
 			}
+			if len(scopeRateLimits) > 0 {
+				if p.ScopeRateLimitCount == nil {
+					p.ScopeRateLimitCount = make(map[string]int64)
+				}
+				for scope := range scopeRateLimits {
+					p.ScopeRateLimitCount[scope]++
+				}
+			}
 		}
 
 		for _, grp := range acc.Groups {
@@ -108,6 +118,14 @@ func (s *OpsService) GetAccountAvailabilityStats(ctx context.Context, platformFi
 			if hasError {
 				g.ErrorCount++
 			}
+			if len(scopeRateLimits) > 0 {
+				if g.ScopeRateLimitCount == nil {
+					g.ScopeRateLimitCount = make(map[string]int64)
+				}
+				for scope := range scopeRateLimits {
+					g.ScopeRateLimitCount[scope]++
+				}
+			}
 		}
 
 		displayGroupID := int64(0)
@@ -140,6 +158,9 @@ func (s *OpsService) GetAccountAvailabilityStats(ctx context.Context, platformFi
 				item.RateLimitRemainingSec = &remainingSec
 			}
 		}
+		if len(scopeRateLimits) > 0 {
+			item.ScopeRateLimits = scopeRateLimits
+		}
 		if isOverloaded && acc.OverloadUntil != nil {
 			item.OverloadUntil = acc.OverloadUntil
 			remainingSec := int64(time.Until(*acc.OverloadUntil).Seconds())