feat!: support Vitest 4

Author: AriPerkkio

README.md

@@ -21,12 +21,12 @@ $ npm install --save-dev @webcontainer/test
 Vitest is also required as peer dependency.
 
 ```sh
-$ npm install --save-dev vitest @vitest/browser
+$ npm install --save-dev vitest
 ```
 
 ## Configuration
 
-Add `vitestWebContainers` plugin in your Vitest config and enable browser mode:
+Add `vitestWebContainers` plugin in your Vitest config and [enable browser mode](https://vitest.dev/guide/browser/#manual-installation):
 
 ```ts
 import { defineConfig } from "vitest/config";

package.json

@@ -49,19 +49,18 @@
     "@webcontainer/snapshot": "^0.1.0"
   },
   "peerDependencies": {
-    "@vitest/browser": "^3.1",
-    "vitest": "^3.1"
+    "vitest": "^4"
   },
   "devDependencies": {
     "@blitz/eslint-plugin": "^0.1.4",
     "@types/node": "^22.14.0",
-    "@vitest/browser": "^3.2.4",
+    "@vitest/browser-playwright": "^4.0.14",
     "eslint": "^9.24.0",
     "playwright": "^1.52.0",
     "prettier": "^3.5.3",
     "tsup": "^8.4.0",
     "typescript": "^5.8.3",
-    "vitest": "^3.2.4"
+    "vitest": "^4.0.14"
   },
   "prettier": {}
 }