feat: integration tests for nodejs generator

[kriscoleman]

feat: integration tests for nodejs generator

Description

A standardized integration testing pattern has been adopted to validate that the CLI's generated feature flag clients are usable and compile within their respective language ecosystems. The Node.js generator is currently missing such integration test coverage.

We should implement integration tests for the Node.js generator using the established pattern outlined in the CLI's testing documentation.

📄 Relevant Documentation:
Integration Testing Pattern

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Tasks

• Set up a minimal Node.js test project (e.g., using npm or yarn)
• Generate a feature flag client using the Node.js generator
• Ensure the generated code compiles (if applicable) and runs without errors
• Write a test to validate a basic flag evaluation
• Integrate the test into the overall integration suite and CI
• Document any Node.js-specific setup if needed

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Acceptance Criteria

• ✅ Node.js generator has at least one integration test
• ✅ Generated Node.js code runs and evaluates flags as expected
• ✅ Integration test executes as part of the CI pipeline
• ✅ The test follows the standard integration testing format

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Additional Notes

While Node.js is dynamically typed, these tests are still valuable for catching runtime issues and ensuring client usability. This effort helps maintain generator reliability and ecosystem parity.

[Adityasinghvats]

Can you assign me this issue?

[Adityasinghvats]

I am taking reference from C# integration test

• Do I need to add dockerfile for nodejs-integration folder as well?

[redpinecube]

@Adityasinghvats I didn't add it in my PR for the Go integration test, I don't think it's necessary. I think Docker was used before Dagger and that file was left over.