feat: complete ESLint v10 migration

[MikeMcC399]

Situation

• The explicit flat configuration option was replaced in eslint-plugin-cypress@5.0.0, in May 2025, by changing the default configuration eslint-plugin-cypress to be equivalent to eslint-plugin-cypress/flat, and at the same time eslint-plugin-cypress/flat was declared deprecated with a notice for planned removal in a future major version.
• "globals": "^16.5.0" is configured in dependencies. The latest version is globals@17.3.0
• package.json currently contains no package type field, although Node.js now recommends in Determining module system that "package authors should always include the "type" field in their package.json files".

Change

• remove deprecated eslint-plugin-cypress/flat configuration and change entry point to neutrally named /lib/index.js
• remove tests associated with eslint-plugin-cypress/flat
• tie links to ESLint documentation for legacy configurations to ESLint v9 docs
• update globals to 17.3.0
• add "type": "commonjs" to package.json
• update Node.js usage to 24.13.1 Active LTS
• replace some internal absolute links in documentation with relative links

[cypress-app-bot]

• Create a Draft Pull Request if your PR is not ready for review. Mark the PR as Ready for Review when you're ready for a Cypress team member to review the PR.

[MikeMcC399]

Branch protection rules may now be changed to include ci/circleci: test-v10

[cypress-app-bot]

🎉 This PR is included in version 5.4.0 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot 📦🚀

[MikeMcC399]

@jennifer-shehane

I made a mistake in the commit body and wrote only BREAKING: instead of BREAKING CHANGE: so now there has been a version 5.4.0 published instead of 6.0.0. Sorry about that!

I guess the best solution would be to republish with BREAKING CHANGE: and to deprecate the 5.4.0 version.

[MikeMcC399]

The breaking changes are thankfully not too severe.

If a system were to automatically upgrade to 5.4.0 and they were still using eslint-plugin-cypress/flat, they would need to remove the /flat suffix.

The update from globals@16 to globals@17 probably will cause no issue.

[MikeMcC399]

Fixed in #299