Upgrade to ESLint v10

[charles4221]

Summary

With our TypeScript rewrite in #579, ESLint was upgraded from v6 to v9.

Since then, v10 has been released as stable:
https://eslint.org/blog/2026/02/eslint-v10.0.0-released/

We should migrate to v10 as soon as practical:
https://eslint.org/docs/latest/use/migrate-to-10.0.0

This will only be possible once each of our ESLint plugin dependencies have been updated to support v10 as well.

Plugin Upgrade Tracker

• eslint-plugin-import

  • Compatibility with ESLint 10 import-js/eslint-plugin-import#3227
  • ESLint v10 support import-js/eslint-plugin-import#3230

• eslint-plugin-jest

  • feat: support ESLint v10 jest-community/eslint-plugin-jest#1929

• eslint-plugin-jsx-a11y

  • [Feature] Support for ESLint v10 jsx-eslint/eslint-plugin-jsx-a11y#1075
  • [New] Add ESLint 10 support jsx-eslint/eslint-plugin-jsx-a11y#1081
    (unofficial)

• eslint-plugin-prettier

  • chore: testing eslint v10 prettier/eslint-plugin-prettier#779

• eslint-plugin-react

  • ESLint v10 compatibility jsx-eslint/eslint-plugin-react#3977
  • Fix ESLint v10 RuleContext API removal (follow-up to #3972) jsx-eslint/eslint-plugin-react#3979

• eslint-plugin-react-hooks

  • [eslint-plugin-react-hooks] Add ESLint v10 support react/react#35720

• eslint-plugin-testing-library

  • No ticket or PR as it apparently Just Works ^TM

• eslint-plugin-unicorn

  • Support ESLint 10 sindresorhus/eslint-plugin-unicorn#2823

• typescript-eslint

  • Enhancement: scope-manager handling globals in ESLint v10 typescript-eslint/typescript-eslint#11762
  • feat(scope-manager): support ScopeManager#addGlobals typescript-eslint/typescript-eslint#11914