fix: 修复批量更新凭证明细与缓存TTL抖动

- BatchUpdateCredentials 返回 success/failed/results 及 success_ids/failed_ids

- billing jitteredTTL 改为只减不增，确保TTL不超上界

- crypto/rand 失败时随机ID降级避免 panic

- OpenAI SelectAccount 失败日志去重并补充字段

- 修复两处类型断言以通过 errcheck

backend/internal/handler/admin/account_handler.go

@@ -810,20 +810,38 @@ func (h *AccountHandler) BatchUpdateCredentials(c *gin.Context) {
 		updates = append(updates, accountUpdate{ID: accountID, Credentials: account.Credentials})
 	}
 
-	// 阶段二：依次更新，任何失败立即返回（避免部分成功部分失败）
+	// 阶段二：依次更新，返回每个账号的成功/失败明细，便于调用方重试
+	success := 0
+	failed := 0
+	successIDs := make([]int64, 0, len(updates))
+	failedIDs := make([]int64, 0, len(updates))
+	results := make([]gin.H, 0, len(updates))
 	for _, u := range updates {
-		updateInput := &service.UpdateAccountInput{
-			Credentials: u.Credentials,
-		}
+		updateInput := &service.UpdateAccountInput{Credentials: u.Credentials}
 		if _, err := h.adminService.UpdateAccount(ctx, u.ID, updateInput); err != nil {
-			response.Error(c, 500, fmt.Sprintf("Failed to update account %d: %v", u.ID, err))
-			return
+			failed++
+			failedIDs = append(failedIDs, u.ID)
+			results = append(results, gin.H{
+				"account_id": u.ID,
+				"success":    false,
+				"error":      err.Error(),
+			})
+			continue
 		}
+		success++
+		successIDs = append(successIDs, u.ID)
+		results = append(results, gin.H{
+			"account_id": u.ID,
+			"success":    true,
+		})
 	}
 
 	response.Success(c, gin.H{
-		"success": len(updates),
-		"failed":  0,
+		"success":     success,
+		"failed":      failed,
+		"success_ids": successIDs,
+		"failed_ids":  failedIDs,
+		"results":     results,
 	})
 }
 

backend/internal/handler/openai_gateway_handler.go

@@ -219,9 +219,8 @@ func (h *OpenAIGatewayHandler) Responses(c *gin.Context) {
 		log.Printf("[OpenAI Handler] Selecting account: groupID=%v model=%s", apiKey.GroupID, reqModel)
 		selection, err := h.gatewayService.SelectAccountWithLoadAwareness(c.Request.Context(), apiKey.GroupID, sessionHash, reqModel, failedAccountIDs)
 		if err != nil {
-			log.Printf("[OpenAI Handler] SelectAccount failed: %v", err)
+			log.Printf("[OpenAI Handler] SelectAccount failed: groupID=%v model=%s tried=%d err=%v", apiKey.GroupID, reqModel, len(failedAccountIDs), err)
 			if len(failedAccountIDs) == 0 {
-				log.Printf("[OpenAI Gateway] SelectAccount failed: %v", err)
 				h.handleStreamingAwareError(c, http.StatusServiceUnavailable, "api_error", "Service temporarily unavailable", streamStarted)
 				return
 			}

backend/internal/pkg/antigravity/response_transformer.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"log"
 	"strings"
+	"time"
 )
 
 // TransformGeminiToClaude 将 Gemini 响应转换为 Claude 格式（非流式）
@@ -345,13 +346,25 @@ func buildGroundingText(grounding *GeminiGroundingMetadata) string {
 // generateRandomID 生成密码学安全的随机 ID
 func generateRandomID() string {
 	const chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"
-	result := make([]byte, 12)
+	id := make([]byte, 12)
 	randBytes := make([]byte, 12)
 	if _, err := rand.Read(randBytes); err != nil {
-		panic("crypto/rand unavailable: " + err.Error())
+		// 避免在请求路径里 panic：极端情况下熵源不可用时降级为伪随机。
+		// 这里主要用于生成响应/工具调用的临时 ID，安全要求不高但需尽量避免碰撞。
+		seed := uint64(time.Now().UnixNano())
+		if err != nil {
+			seed ^= uint64(len(err.Error())) << 32
+		}
+		for i := range id {
+			seed ^= seed << 13
+			seed ^= seed >> 7
+			seed ^= seed << 17
+			id[i] = chars[int(seed)%len(chars)]
+		}
+		return string(id)
 	}
 	for i, b := range randBytes {
-		result[i] = chars[int(b)%len(chars)]
+		id[i] = chars[int(b)%len(chars)]
 	}
-	return string(result)
+	return string(id)
 }

backend/internal/repository/billing_cache.go

@@ -22,8 +22,12 @@ const (
 
 // jitteredTTL 返回带随机抖动的 TTL，防止缓存雪崩
 func jitteredTTL() time.Duration {
-	jitter := time.Duration(rand.Int63n(int64(2*billingCacheJitter))) - billingCacheJitter
-	return billingCacheTTL + jitter
+	// 只做“减法抖动”，确保实际 TTL 不会超过 billingCacheTTL（避免上界预期被打破）。
+	if billingCacheJitter <= 0 {
+		return billingCacheTTL
+	}
+	jitter := time.Duration(rand.Int63n(int64(billingCacheJitter)))
+	return billingCacheTTL - jitter
 }
 
 // billingBalanceKey generates the Redis key for user balance cache.

backend/internal/service/sse_scanner_buffer_pool.go

@@ -13,7 +13,12 @@ var sseScannerBuf64KPool = sync.Pool{
 }
 
 func getSSEScannerBuf64K() *sseScannerBuf64K {
-	return sseScannerBuf64KPool.Get().(*sseScannerBuf64K)
+	v := sseScannerBuf64KPool.Get()
+	buf, ok := v.(*sseScannerBuf64K)
+	if !ok || buf == nil {
+		return new(sseScannerBuf64K)
+	}
+	return buf
 }
 
 func putSSEScannerBuf64K(buf *sseScannerBuf64K) {

backend/internal/service/subscription_service.go

@@ -483,7 +483,11 @@ func (s *SubscriptionService) GetActiveSubscription(ctx context.Context, userID,
 		return nil, err
 	}
 	// singleflight 返回的也是缓存指针，需要浅拷贝
-	cp := *value.(*UserSubscription)
+	sub, ok := value.(*UserSubscription)
+	if !ok || sub == nil {
+		return nil, ErrSubscriptionNotFound
+	}
+	cp := *sub
 	return &cp, nil
 }