Add vitest.config.ts

Author: razor-x

tsconfig.json

@@ -30,5 +30,5 @@
     }
   },
   "files": ["src/index.ts"],
-  "include": ["src/**/*", "test/**/*", "examples/**/*"]
+  "include": ["src/**/*", "test/**/*", "examples/**/*", "vitest.config.ts"]
 }

vitest.config.ts

@@ -0,0 +1,7 @@
+import { defineConfig } from 'vitest/config'
+
+export default defineConfig({
+  test: {
+    environment: 'happy-dom',
+  },
+})