fix(theme): add path-browserify as explicit dependency

Required by the path resolve.fallback added in configureWebpack to
support postman-code-generators 2.1.1+ browser bundling.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: sserrata

packages/docusaurus-theme-openapi-docs/package.json

@@ -47,6 +47,7 @@
     "@reduxjs/toolkit": "^2.8.2",
     "allof-merge": "^0.6.6",
     "buffer": "^6.0.3",
+    "path-browserify": "^1.0.1",
     "clsx": "^2.1.1",
     "copy-text-to-clipboard": "^3.2.0",
     "crypto-js": "^4.2.0",