fix(acceptance): 为高并发验收启用有界排队

生产同构 Gemini 千请求在真实候选并发饱和后因 queueing disabled 返回 429，同时单台压测机建立千条 WAN TCP 产生连接层 reset。仅对 acceptance 与 acceptance_canary 覆盖为 10000 条、最长 15 分钟的有界等待队列，保留候选原始并发和 RPM/TPM 上限；压测传输强制 HTTP/2 复用连接，避免单源连接风暴。正式 production 策略不变。\n\n验证：acceptance-load 与 runner 定向测试通过，新增生产策略不变和验收队列边界单测；gofmt、bash -n、ShellCheck、git diff --check 通过。

apps/api/internal/runner/admission_test.go

@@ -1,6 +1,10 @@
 package runner
 
-import "testing"
+import (
+	"testing"
+
+	"github.com/easyai/easyai-ai-gateway/apps/api/internal/store"
+)
 
 func TestDistributedAdmissionModelTypeBoundary(t *testing.T) {
 	for _, modelType := range []string{
@@ -19,3 +23,41 @@ func TestDistributedAdmissionModelTypeBoundary(t *testing.T) {
 		}
 	}
 }
+
+func TestAcceptanceAdmissionScopesEnableBoundedQueueWithoutChangingConcurrency(t *testing.T) {
+	input := []store.AdmissionScope{{
+		ScopeType:       "platform_model",
+		ScopeKey:        "model-1",
+		ConcurrentLimit: 10,
+		QueueLimit:      0,
+		MaxWaitSeconds:  0,
+	}}
+
+	got := acceptanceAdmissionScopes(store.GatewayTask{RunMode: "acceptance"}, input)
+
+	if got[0].ConcurrentLimit != 10 {
+		t.Fatalf("acceptance must preserve the production concurrency limit, got %+v", got[0])
+	}
+	if got[0].QueueLimit != acceptanceQueueLimit || got[0].MaxWaitSeconds != acceptanceQueueMaxWait {
+		t.Fatalf("acceptance must enable a bounded queue, got %+v", got[0])
+	}
+	if input[0].QueueLimit != 0 || input[0].MaxWaitSeconds != 0 {
+		t.Fatalf("acceptance queue overlay must not mutate the production scopes, got %+v", input[0])
+	}
+}
+
+func TestAcceptanceAdmissionScopesLeaveProductionPolicyUnchanged(t *testing.T) {
+	input := []store.AdmissionScope{{
+		ScopeType:       "platform_model",
+		ScopeKey:        "model-1",
+		ConcurrentLimit: 10,
+		QueueLimit:      3,
+		MaxWaitSeconds:  7,
+	}}
+
+	got := acceptanceAdmissionScopes(store.GatewayTask{RunMode: "production"}, input)
+
+	if got[0].QueueLimit != 3 || got[0].MaxWaitSeconds != 7 || got[0].ConcurrentLimit != 10 {
+		t.Fatalf("production admission policy changed: %+v", got[0])
+	}
+}