fix: use a standalone config file for the vitest (#227)

Co-authored-by: Haoqun Jiang <[email protected]>

Fixes #221 
Fixes #199

Author: btea

Diff for: template/config/vitest/package.json

@@ -1,6 +1,6 @@
 {
   "scripts": {
-    "test:unit": "vitest --environment jsdom --root src/"
+    "test:unit": "vitest"
   },
   "dependencies": {
     "vue": "^3.2.47"

Diff for: template/config/vitest/vitest.config.js

@@ -0,0 +1,15 @@
+import { fileURLToPath } from 'node:url'
+import { mergeConfig } from 'vite'
+import { configDefaults, defineConfig } from 'vitest/config'
+import viteConfig from './vite.config'
+
+export default mergeConfig(
+  viteConfig,
+  defineConfig({
+    test: {
+      environment: 'jsdom',
+      exclude: [...configDefaults.exclude, 'e2e/*'],
+      root: fileURLToPath(new URL('./', import.meta.url))
+    }
+  })
+)