fix(circuit-breaker): vendor type CB respects ENABLE_ENDPOINT_CIRCUIT_BREAKER

Make vendor type circuit breaker controlled by the same
ENABLE_ENDPOINT_CIRCUIT_BREAKER switch as endpoint circuit breaker.
When disabled (default), vendor type CB will never trip or block
providers, resolving user confusion about "vendor type temporary
circuit breaker" skip reasons in decision chain.

Changes:
- Add ENABLE_ENDPOINT_CIRCUIT_BREAKER check in isVendorTypeCircuitOpen()
- Add switch check in recordVendorTypeAllEndpointsTimeout()
- Add tests for switch on/off behavior

Co-Authored-By: Claude Sonnet 4.5 <[email protected]>

src/lib/vendor-type-circuit-breaker.ts

@@ -1,5 +1,6 @@
 import "server-only";
 
+import { getEnvConfig } from "@/lib/config/env.schema";
 import { logger } from "@/lib/logger";
 import {
   deleteVendorTypeCircuitState,
@@ -116,6 +117,11 @@ export async function isVendorTypeCircuitOpen(
   vendorId: number,
   providerType: ProviderType
 ): Promise<boolean> {
+  // 检查端点熔断器开关，供应商类型熔断复用此开关
+  if (!getEnvConfig().ENABLE_ENDPOINT_CIRCUIT_BREAKER) {
+    return false;
+  }
+
   const state = await getOrCreateState(vendorId, providerType);
 
   if (state.manualOpen) {
@@ -141,6 +147,11 @@ export async function recordVendorTypeAllEndpointsTimeout(
   providerType: ProviderType,
   openDurationMs: number = AUTO_OPEN_DURATION_MS
 ): Promise<void> {
+  // 检查端点熔断器开关，供应商类型熔断复用此开关
+  if (!getEnvConfig().ENABLE_ENDPOINT_CIRCUIT_BREAKER) {
+    return;
+  }
+
   const state = await getOrCreateState(vendorId, providerType);
 
   if (state.manualOpen) {

tests/unit/lib/vendor-type-circuit-breaker.test.ts

@@ -24,6 +24,88 @@ afterEach(() => {
 });
 
 describe("vendor-type-circuit-breaker", () => {
+  test("ENABLE_ENDPOINT_CIRCUIT_BREAKER=false 时，isVendorTypeCircuitOpen 始终返回 false", async () => {
+    vi.useFakeTimers();
+    vi.setSystemTime(new Date("2026-01-01T00:00:00.000Z"));
+
+    vi.resetModules();
+
+    const loadMock = vi.fn(async () => null);
+    const saveMock = vi.fn(async () => {});
+
+    vi.doMock("@/lib/logger", () => ({ logger: createLoggerMock() }));
+    vi.doMock("@/lib/redis/vendor-type-circuit-breaker-state", () => ({
+      loadVendorTypeCircuitState: loadMock,
+      saveVendorTypeCircuitState: saveMock,
+      deleteVendorTypeCircuitState: vi.fn(async () => {}),
+    }));
+    vi.doMock("@/lib/config/env.schema", () => ({
+      getEnvConfig: () => ({
+        ENABLE_ENDPOINT_CIRCUIT_BREAKER: false,
+        NODE_ENV: "test",
+      }),
+    }));
+
+    const { isVendorTypeCircuitOpen, recordVendorTypeAllEndpointsTimeout } = await import(
+      "@/lib/vendor-type-circuit-breaker"
+    );
+
+    // 尝试记录熔断
+    await recordVendorTypeAllEndpointsTimeout(100, "claude", 60000);
+    // 不应调用 save
+    expect(saveMock).not.toHaveBeenCalled();
+
+    // 应始终返回 false
+    expect(await isVendorTypeCircuitOpen(100, "claude")).toBe(false);
+  });
+
+  test("ENABLE_ENDPOINT_CIRCUIT_BREAKER=true 时，熔断功能正常工作", async () => {
+    vi.useFakeTimers();
+    vi.setSystemTime(new Date("2026-01-01T00:00:00.000Z"));
+
+    vi.resetModules();
+
+    let redisState: SavedVendorTypeCircuitState | null = null;
+    const loadMock = vi.fn(async () => redisState);
+    const saveMock = vi.fn(
+      async (
+        _vendorId: number,
+        _providerType: ProviderType,
+        state: SavedVendorTypeCircuitState
+      ) => {
+        redisState = state;
+      }
+    );
+
+    vi.doMock("@/lib/logger", () => ({ logger: createLoggerMock() }));
+    vi.doMock("@/lib/redis/vendor-type-circuit-breaker-state", () => ({
+      loadVendorTypeCircuitState: loadMock,
+      saveVendorTypeCircuitState: saveMock,
+      deleteVendorTypeCircuitState: vi.fn(async () => {}),
+    }));
+    vi.doMock("@/lib/config/env.schema", () => ({
+      getEnvConfig: () => ({
+        ENABLE_ENDPOINT_CIRCUIT_BREAKER: true,
+        NODE_ENV: "test",
+      }),
+    }));
+
+    const { isVendorTypeCircuitOpen, recordVendorTypeAllEndpointsTimeout } = await import(
+      "@/lib/vendor-type-circuit-breaker"
+    );
+
+    // 记录熔断
+    await recordVendorTypeAllEndpointsTimeout(101, "claude", 60000);
+    expect(saveMock).toHaveBeenCalled();
+
+    // 应返回 true
+    expect(await isVendorTypeCircuitOpen(101, "claude")).toBe(true);
+
+    // 等待熔断过期
+    vi.advanceTimersByTime(60000 + 1);
+    expect(await isVendorTypeCircuitOpen(101, "claude")).toBe(false);
+  });
+
   test("manual open 时 isVendorTypeCircuitOpen 始终为 true，且自动 open 不应覆盖", async () => {
     vi.useFakeTimers();
     vi.setSystemTime(new Date("2026-01-01T00:00:00.000Z"));