fix: add missing chokidar dependency to package.json

The chokidar package is imported in bin/cli.js for the watch functionality but was not listed in dependencies. This caused ERR_MODULE_NOT_FOUND errors when the package was installed globally.

Fixes the issue where users would see 'Cannot find package chokidar' error when running fetch-client-generator after global installation.

Author: claude

package.json

@@ -20,6 +20,7 @@
   "author": "",
   "license": "ISC",
   "dependencies": {
+    "chokidar": "^4.0.3",
     "commander": "^14.0.0"
   },
   "devDependencies": {