chore(deps): update vitest monorepo to v4

Author: renovate[bot]

package.json

@@ -36,7 +36,7 @@
     "@types/node": "^24.5.2",
     "@types/sse": "^0.0.0",
     "@types/ws": "^8.18.1",
-    "@vitest/coverage-v8": "^3.2.4",
+    "@vitest/coverage-v8": "^4.0.16",
     "async": "^3.2.6",
     "changelogen": "^0.6.2",
     "concat-stream": "^2.0.0",
@@ -53,7 +53,7 @@
     "sse": "^0.0.8",
     "typescript": "^5.9.2",
     "unbuild": "^3.6.1",
-    "vitest": "^3.2.4",
+    "vitest": "^4.0.16",
     "ws": "^8.18.3"
   },
   "packageManager": "pnpm@10.17.1"