Fix ESLint plugin dependencies

[mariozenmedina]

Description of the Change

Draft for maintainer feedback: this PR focuses only on fixing ESLint dependency resolution so wp-scripts lint-js can load the project configs. It does not attempt to fix the existing lint violations that are surfaced afterward.

The root .eslintrc extends plugin:@wordpress/eslint-plugin/recommended, but @wordpress/eslint-plugin was only available as a nested dependency of @wordpress/scripts. Because ESLint resolves plugins from the project config location, it could not find the WordPress ESLint plugin from the project root.

There is a similar issue for Cypress linting: tests/cypress/.eslintrc extends plugin:cypress/recommended, but eslint-plugin-cypress was not declared as a project dependency.

After making those plugins resolvable, ESLint also reaches the WordPress config's TypeScript import resolver setup. The newer resolver interface is not compatible with this project's current ESLint 8 / eslint-plugin-import stack, causing:

Resolve error: typescript with invalid interface loaded as resolver

This PR pins eslint-import-resolver-typescript to 3.5.5, which is compatible with the current ESLint stack.

After this change, wp-scripts lint-js loads the configs/plugins successfully and reaches the existing lint violations, mostly CRLF/Prettier-related formatting errors, which are outside the scope of this PR.

Closes #352

How to test the Change

Using Node 20, matching .nvmrc:

1. Run npm ci.
2. Run npx wp-scripts lint-js.

Expected result:

• ESLint should no longer fail with missing plugin errors for @wordpress/eslint-plugin or eslint-plugin-cypress.
• ESLint should no longer fail with Resolve error: typescript with invalid interface loaded as resolver.
• The command may still report existing lint violations, such as CRLF/Prettier formatting errors, which are outside the scope of this PR.

I also validated config loading with:

• ./node_modules/.bin/eslint --print-config assets/js/blocks.js
• ./node_modules/.bin/eslint --print-config tests/cypress/support/index.js

Changelog Entry

Fixed - ESLint plugin dependency resolution for WordPress and Cypress lint configs.

Credits

Props @mariozenmedina

Checklist:

• I agree to follow this project's Code of Conduct.
• I have updated the documentation accordingly.
• I have added Critical Flows, Test Cases, and/or End-to-End Tests to cover my change.
• All new and existing tests pass.

Documentation and new tests were not added because this is a development dependency/configuration fix. Existing linting still reports pre-existing formatting issues after the dependency resolution problem is fixed.

[mariozenmedina]

I accidentally clicked "Ready for review" while this PR was originally opened as a draft for maintainer feedback. I’ll leave it ready for now to avoid extra status noise, but the intended scope is still the same: this only fixes ESLint dependency/config resolution and does not address the existing lint violations. Feedback on whether this is the right direction is very welcome.