Typescript-operations with `immutableTypes` being true is not using `ReadonlyArray` for input types

[vinassefranche]

Which packages are impacted by your issue?

@graphql-codegen/typescript-operations

Describe the bug

When setting immutableTypes to true in the config of the plugin typescript-operations, the result types for an input having a list is Array instead of ReadonlyArray.
It works well for not input types though.

Your Example Website or App

https://github.com/vinassefranche/codegen-immutable-types-not-set-on-input

Steps to Reproduce the Bug or Issue

1. run pnpm run generate
2. look at the generated types.ts file
3. see the type of SomeInput['books'] using Array<string>

Expected behavior

the type of SomeInput['books'] should use ReadonlyArray<string>

Screenshots or Videos

No response

Platform

• OS: Linux
• NodeJS: 24.15.0
• graphql version: 16.10.0
• @graphql-codegen/* version(s): 7.0.0

Codegen Config File

import {CodegenConfig} from '@graphql-codegen/cli';

const config: CodegenConfig = {
  schema: 'schema.graphql',
  documents: 'document.graphql',
  generates: {
    'types.ts': {
      plugins: ['typescript-operations'],
      config: {
        immutableTypes: true,
      }
    },
  },
};

export default config;

Additional context

Here's a pull request that attempts to fix the issue: #10806

[eddeee888]

Thank you @vinassefranche !
This is released here: https://github.com/dotansimha/graphql-code-generator/releases/tag/release-1781533822235