Upgrade Jest to v30

[jozefizso]

Describe

We should upgrade Jest to v30 as it improves support for testing ESM module packages which will help us upgrade the code in the future.

What’s New in Jest 30?

Jest 30 is noticeably faster, uses less memory, and comes with tons of new features. First, let’s take a look at the breaking changes:

Breaking Changes

• Jest 30 drops support for Node 14, 16, 19, and 21.
• The minimum compatible TypeScript version is now 5.4.
• Various expect aliases were removed.
• Jest now supports .mts and .cts files by default.

Proposed solution

References:

• https://jestjs.io/docs/upgrading-to-jest30
• https://jestjs.io/blog/2025/06/04/jest-30
• https://github.com/jest-community/eslint-plugin-jest/blob/HEAD/docs/rules/no-alias-methods.md