fix: check run dir exists before read it (#33)

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->

## Summary by CodeRabbit

- **New Features**
	- Introduced a simplified existence check for the `rundir` directory.
  
- **Chores**
- Updated the `utility` dependency version in the project configuration.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

agent.js

@@ -2,12 +2,13 @@ const path = require('node:path');
 const fs = require('node:fs/promises');
 const debounce = require('debounce');
 const multimatch = require('multimatch');
+const { exists } = require('utility');
 
 module.exports = agent => {
   // clean all timing json
   agent.beforeStart(async () => {
     const rundir = agent.config.rundir;
-    const stat = await fs.stat(rundir, { throwIfNoEntry: false });
+    const stat = await exists(rundir);
     if (!stat) return;
     const files = await fs.readdir(rundir);
     for (const file of files) {

package.json

@@ -20,7 +20,7 @@
   "dependencies": {
     "debounce": "^1.1.0",
     "multimatch": "^5.0.0",
-    "utility": "^2.3.0"
+    "utility": "^2.4.0"
   },
   "devDependencies": {
     "@types/node": "^22.10.2",