fix(test): route serial runs through scoped vitest lanes

test/vitest-projects-config.test.ts

@@ -8,6 +8,7 @@ import baseConfig, { rootVitestProjects } from "./vitest/vitest.config.ts";
 import { createContractsVitestConfig } from "./vitest/vitest.contracts.config.ts";
 import { createGatewayVitestConfig } from "./vitest/vitest.gateway.config.ts";
 import { createPluginSdkLightVitestConfig } from "./vitest/vitest.plugin-sdk-light.config.ts";
+import { sharedVitestConfig } from "./vitest/vitest.shared.config.ts";
 import { createUiVitestConfig } from "./vitest/vitest.ui.config.ts";
 import { createUnitFastVitestConfig } from "./vitest/vitest.unit-fast.config.ts";
 import { createUnitVitestConfig } from "./vitest/vitest.unit.config.ts";
@@ -17,6 +18,11 @@ describe("projects vitest config", () => {
     expect(baseConfig.test?.projects).toEqual([...rootVitestProjects]);
   });
 
+  it("disables vite env-file loading for vitest lanes", () => {
+    expect(baseConfig.envFile).toBe(false);
+    expect(sharedVitestConfig.envFile).toBe(false);
+  });
+
   it("keeps root projects on their expected pool defaults", () => {
     expect(createGatewayVitestConfig().test.pool).toBe("threads");
     expect(createAgentsVitestConfig().test.pool).toBe("threads");

test/vitest/vitest.shared.config.ts

@@ -184,6 +184,7 @@ if (!isCI && localScheduling.throttledBySystem && shouldPrintVitestThrottle(proc
 
 export const sharedVitestConfig = {
   root: repoRoot,
+  envFile: false,
   resolve: {
     alias: [
       {