test: restrict webview-ui workers in CI to prevent JSDOM CPU starvation

Author: Test User

webview-ui/vitest.config.ts

@@ -4,6 +4,7 @@ import path from "path"
 import { resolveVerbosity } from "../src/utils/vitest-verbosity"
 
 const { silent, reporters, onConsoleLog } = resolveVerbosity()
+const isCI = process.env.CI === "true"
 
 export default defineConfig({
 	plugins: [react()],
@@ -16,6 +17,8 @@ export default defineConfig({
 		environment: "jsdom",
 		include: ["src/**/*.spec.ts", "src/**/*.spec.tsx"],
 		onConsoleLog,
+		maxWorkers: isCI ? 1 : undefined,
+		testTimeout: isCI ? 15000 : 5000,
 		server: {
 			deps: {
 				inline: ["@radix-ui/react-slot"],