BUG: Crash on some dependencies

[GonozalIX]

For some dependencies the license-checker crashes with a TypeError.

Description

In our case we are using the docosaurus plugin @scalar/docusaurus in the current version.
If we run the license-checker it crashes with the error:

TypeError: json.readme.toLowerCase is not a function
    at flatten (node_modules/.pnpm/license-checker@25.0.1/node_modules/license-checker/lib/index.js:115:51)

Checked the line and made some debug:

if (json.path && (!json.readme || json.readme.toLowerCase().indexOf('no readme data found') > -1)) {

json.readme seems to be expected as a string, but for @scalar/docusaurus it contains

{
  title: 'Scalar API Reference Plugin for Docusaurus',
  badges: [
    { type: 'npm-version' },
    { type: 'npm-downloads' },
    { type: 'npm-license' }
  ],
  documentation: 'https://scalar.com/products/api-references/integrations/docusaurus',
  image: {
    url: 'https://github.com/scalar/scalar/blob/main/integrations/docusaurus/docusaurus.png?raw=true',
    altText: 'Screenshot of the Docusaurus integration'
  }
}

which is not.

Expected Behavior

license-checker should not crash on any dependency

Actual Behavior

It crashes at least for @scalar/docusaurus

Possible Fix

Check if json.readme is a string.

Steps to Reproduce

use as package.json

{
  "name": "crash-it",
  "version": "1.0.0",
  "private": true,
  "dependencies": {
    "@onebeyond/license-checker": "^2",
    "@scalar/docusaurus": "^0"
  }
}

and run

npm install
npx @onebeyond/license-checker --failOn MIT

Your Environment

• Version used: 2.2.0
• Environment name and version (e.g. Chrome 39, node.js 5.4): node 24.16.0
• Operating System and version (desktop or mobile): Ubuntu 22.04