feat: type _getJSONData method

[nicoabie]

fixes #323

[Copilot]

Pull Request Overview

This PR adds type annotations to the _getJSONData method, specifically focusing on improving type safety for Express response objects with generic type parameters. The changes introduce test cases to verify proper typing behavior when using Express responses with custom data structures.

• Adds type tests for Express responses with generic type parameters
• Validates type safety for createResponse and createMocks functions with typed responses

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[eugef]

Hi @nicoabie thanks for your PR.

I want to make sure this change doesn’t require updating any existing tests that depend on the any type of _getJSONData. Is that correct?

[nicoabie]

Hi @nicoabie thanks for your PR.

I want to make sure this change doesn’t require updating any existing tests that depend on the any type of _getJSONData. Is that correct?

Yes, no need to change any existing tests, it uses any if no type is specified and specification is optional.