fix: Grok 长上下文只跟分组开关，不受 OpenAI 账号开关否决

openai_long_context_billing_enabled 是 OpenAI 账号设置，Grok
账号无法打开。按账号硬传 false 会让分组开关失效，官方 200k
阶梯和渠道多档区间全部塌到第一档。非 OpenAI 不再传账号门闩。

backend/internal/service/openai_alpha_search_billing_test.go

@@ -50,7 +50,7 @@ func TestCalculateOpenAIRecordUsageCostWebSearchPerCall(t *testing.T) {
 	// 即使 token 倍率（含高峰，3.0）更高也不采用。
 	apiKey := &APIKey{ID: 1, GroupID: &groupID, Group: &Group{ID: groupID, Platform: PlatformOpenAI}}
 	result := &OpenAIForwardResult{Model: "gpt-5.6-sol", UpstreamModel: "gpt-5.6-sol", WebSearchCalls: 1}
-	cost, err := svc.calculateOpenAIRecordUsageCost(context.Background(), result, apiKey, []string{"gpt-5.6-sol"}, 3.0, 1.0, 1.0, 2.0, UsageTokens{}, "", false)
+	cost, err := svc.calculateOpenAIRecordUsageCost(context.Background(), result, apiKey, []string{"gpt-5.6-sol"}, 3.0, 1.0, 1.0, 2.0, UsageTokens{}, "", boolPtr(false))
 	require.NoError(t, err)
 	require.Equal(t, string(BillingModePerRequest), cost.BillingMode)
 	require.InDelta(t, 0.01, cost.TotalCost, 1e-12)
@@ -58,7 +58,7 @@ func TestCalculateOpenAIRecordUsageCostWebSearchPerCall(t *testing.T) {
 
 	// 分组配置单价 0.005
 	apiKey.Group.WebSearchPricePerCall = float64Ptr(0.005)
-	cost, err = svc.calculateOpenAIRecordUsageCost(context.Background(), result, apiKey, []string{"gpt-5.6-sol"}, 1.0, 1.0, 1.0, 1.0, UsageTokens{}, "", false)
+	cost, err = svc.calculateOpenAIRecordUsageCost(context.Background(), result, apiKey, []string{"gpt-5.6-sol"}, 1.0, 1.0, 1.0, 1.0, UsageTokens{}, "", boolPtr(false))
 	require.NoError(t, err)
 	require.InDelta(t, 0.005, cost.TotalCost, 1e-12)
 	require.InDelta(t, 0.005, cost.ActualCost, 1e-12)
@@ -66,7 +66,7 @@ func TestCalculateOpenAIRecordUsageCostWebSearchPerCall(t *testing.T) {
 	// WebSearchCalls = 0 时不得走按次分支（无定价数据会返回 pricing 错误，
 	// 证明回落到了 token 路径而不是被按次分支吞掉）。
 	result.WebSearchCalls = 0
-	_, err = svc.calculateOpenAIRecordUsageCost(context.Background(), result, apiKey, []string{"gpt-5.6-sol"}, 1.0, 1.0, 1.0, 1.0, UsageTokens{InputTokens: 10}, "", false)
+	_, err = svc.calculateOpenAIRecordUsageCost(context.Background(), result, apiKey, []string{"gpt-5.6-sol"}, 1.0, 1.0, 1.0, 1.0, UsageTokens{InputTokens: 10}, "", boolPtr(false))
 	require.Error(t, err)
 }
 

backend/internal/service/openai_gateway_record_usage_test.go

@@ -1210,6 +1210,58 @@ func TestOpenAIGatewayServiceRecordUsage_GroupAndAccountLongContextMustBothAllow
 	})
 }
 
+// openai_long_context_billing_enabled is an OpenAI-only account setting, so it
+// must not veto the official Grok >=200k ladder: a Grok account has no way to
+// ever set that flag, which would make the group toggle unreachable.
+func TestOpenAIGatewayServiceRecordUsage_GrokLongContextFollowsGroupToggleOnly(t *testing.T) {
+	baseInput := 250000 * 2e-6
+	baseOutput := 1000 * 6e-6
+
+	grokAccount := func(id int64) *Account {
+		return &Account{ID: id, Platform: PlatformGrok, Type: AccountTypeOAuth}
+	}
+
+	t.Run("group on applies the official ladder", func(t *testing.T) {
+		usageRepo := &openAIRecordUsageLogRepoStub{inserted: true}
+		svc := newOpenAIRecordUsageServiceForTest(usageRepo, &openAIRecordUsageUserRepoStub{}, &openAIRecordUsageSubRepoStub{}, nil)
+		err := svc.RecordUsage(context.Background(), &OpenAIRecordUsageInput{
+			Result: &OpenAIForwardResult{
+				RequestID: "resp_grok_longctx_on",
+				Usage:     OpenAIUsage{InputTokens: 250000, OutputTokens: 1000},
+				Model:     "grok-4.5",
+				Duration:  time.Second,
+			},
+			APIKey:  openAIRecordUsageAPIKeyWithGroup(svc, 1030, true),
+			User:    &User{ID: 2030},
+			Account: grokAccount(3030),
+		})
+		require.NoError(t, err)
+		require.True(t, usageRepo.lastLog.LongContextBillingApplied)
+		require.InDelta(t, baseInput*2, usageRepo.lastLog.InputCost, 1e-10)
+		require.InDelta(t, baseOutput*2, usageRepo.lastLog.OutputCost, 1e-10)
+	})
+
+	t.Run("group off keeps the base card", func(t *testing.T) {
+		usageRepo := &openAIRecordUsageLogRepoStub{inserted: true}
+		svc := newOpenAIRecordUsageServiceForTest(usageRepo, &openAIRecordUsageUserRepoStub{}, &openAIRecordUsageSubRepoStub{}, nil)
+		err := svc.RecordUsage(context.Background(), &OpenAIRecordUsageInput{
+			Result: &OpenAIForwardResult{
+				RequestID: "resp_grok_longctx_off",
+				Usage:     OpenAIUsage{InputTokens: 250000, OutputTokens: 1000},
+				Model:     "grok-4.5",
+				Duration:  time.Second,
+			},
+			APIKey:  openAIRecordUsageAPIKeyWithGroup(svc, 1031, false),
+			User:    &User{ID: 2031},
+			Account: grokAccount(3031),
+		})
+		require.NoError(t, err)
+		require.False(t, usageRepo.lastLog.LongContextBillingApplied)
+		require.InDelta(t, baseInput, usageRepo.lastLog.InputCost, 1e-10)
+		require.InDelta(t, baseOutput, usageRepo.lastLog.OutputCost, 1e-10)
+	})
+}
+
 func TestOpenAIGatewayServiceRecordUsage_SparkShadowUsesCurrentParentBillingSetting(t *testing.T) {
 	tests := []struct {
 		name          string

backend/internal/service/openai_gateway_search_surcharge_test.go

@@ -36,7 +36,7 @@ func TestCalculateOpenAIRecordUsageCost_SearchIsAdditiveToTokens(t *testing.T) {
 		1.0,
 		UsageTokens{InputTokens: 1000, OutputTokens: 500},
 		"",
-		false,
+		boolPtr(false),
 	)
 	require.NoError(t, err)
 	require.NotNil(t, cost)
@@ -66,7 +66,7 @@ func TestCalculateOpenAIRecordUsageCost_SearchOnlyWhenNoTokenPricing(t *testing.
 		1.0,
 		UsageTokens{},
 		"",
-		false,
+		boolPtr(false),
 	)
 	require.NoError(t, err)
 	require.NotNil(t, cost)
@@ -111,7 +111,7 @@ func TestCalculateOpenAIRecordUsageCost_TokenPricingErrorNotSwallowedBySearch(t
 		1.0,
 		UsageTokens{InputTokens: 1000, OutputTokens: 500},
 		"",
-		false,
+		boolPtr(false),
 	)
 	require.Error(t, err)
 	require.Nil(t, cost)

backend/internal/service/openai_gateway_usage.go

@@ -211,7 +211,7 @@ func (s *OpenAIGatewayService) RecordUsage(ctx context.Context, input *OpenAIRec
 			return err
 		}
 	}
-	longContextBillingEnabled := billingAccount.IsOpenAILongContextBillingEnabled()
+	longContextBillingGate := openAILongContextBillingGate(billingAccount)
 	cost, err = s.calculateOpenAIRecordUsageCost(
 		ctx,
 		result,
@@ -223,7 +223,7 @@ func (s *OpenAIGatewayService) RecordUsage(ctx context.Context, input *OpenAIRec
 		baseMultiplier,
 		tokens,
 		serviceTier,
-		longContextBillingEnabled,
+		longContextBillingGate,
 	)
 	if err != nil {
 		if !isUsagePricingUnavailableError(err) {
@@ -256,7 +256,7 @@ func (s *OpenAIGatewayService) RecordUsage(ctx context.Context, input *OpenAIRec
 			responseModels := usageBillingModelCandidates(responseModel)
 			responseCost, responseErr := s.calculateOpenAIRecordUsageCost(
 				ctx, result, apiKey, responseModels, multiplier, imageMultiplier,
-				videoMultiplier, baseMultiplier, tokens, serviceTier, longContextBillingEnabled,
+				videoMultiplier, baseMultiplier, tokens, serviceTier, longContextBillingGate,
 			)
 			// 基线定价源以 baselineBillingModel 为准：它正是 calculateOpenAIRecordUsageCost
 			// 内部做渠道定价判断时使用的模型，且"首候选有渠道价"必然意味着首候选就是实际
@@ -480,6 +480,19 @@ func (s *OpenAIGatewayService) hasIdentifiedOpenAIResponsePricing(ctx context.Co
 	return s.billingService.HasIdentifiedTokenPricing(model), false
 }
 
+// openAILongContextBillingGate returns the per-account long-context opt-in.
+// The flag is an OpenAI-only account setting, so other platforms (Grok) return
+// nil — "no per-account gate" — and are governed by the group toggle alone.
+// Returning a hardcoded false for them would veto the official model ladders
+// (e.g. the Grok >=200k 2x card) that no account setting can ever re-enable.
+func openAILongContextBillingGate(account *Account) *bool {
+	if account == nil || !account.IsOpenAI() {
+		return nil
+	}
+	enabled := account.IsOpenAILongContextBillingEnabled()
+	return &enabled
+}
+
 func (s *OpenAIGatewayService) calculateOpenAIRecordUsageCost(
 	ctx context.Context,
 	result *OpenAIForwardResult,
@@ -491,7 +504,7 @@ func (s *OpenAIGatewayService) calculateOpenAIRecordUsageCost(
 	webSearchMultiplier float64,
 	tokens UsageTokens,
 	serviceTier string,
-	longContextBillingEnabled bool,
+	longContextBillingGate *bool,
 ) (*CostBreakdown, error) {
 	billingModel := firstUsageBillingModel(billingModels)
 	if result != nil && result.WebSearchCalls > 0 {
@@ -543,7 +556,7 @@ func (s *OpenAIGatewayService) calculateOpenAIRecordUsageCost(
 				multiplier,
 				tokens,
 				serviceTier,
-				longContextBillingEnabled,
+				longContextBillingGate,
 			)
 			if err == nil {
 				tokenCost = cost
@@ -632,7 +645,7 @@ func (s *OpenAIGatewayService) calculateOpenAIRecordUsageTokenCost(
 	multiplier float64,
 	tokens UsageTokens,
 	serviceTier string,
-	longContextBillingEnabled bool,
+	longContextBillingGate *bool,
 ) (*CostBreakdown, error) {
 	if s.resolver != nil && apiKey.Group != nil {
 		gid := apiKey.Group.ID
@@ -640,7 +653,7 @@ func (s *OpenAIGatewayService) calculateOpenAIRecordUsageTokenCost(
 			Ctx: ctx, Model: billingModel, GroupID: &gid, Group: apiKey.Group,
 			Tokens: tokens, RequestCount: 1, RateMultiplier: multiplier,
 			ServiceTier: serviceTier, Resolver: s.resolver,
-			LongContextBillingEnabled: &longContextBillingEnabled,
+			LongContextBillingEnabled: longContextBillingGate,
 		})
 	}
 	return s.billingService.calculateCostWithServiceTierPolicy(
@@ -648,7 +661,7 @@ func (s *OpenAIGatewayService) calculateOpenAIRecordUsageTokenCost(
 		tokens,
 		multiplier,
 		serviceTier,
-		longContextBillingEnabled,
+		longContextBillingGate == nil || *longContextBillingGate,
 	)
 }