refactor(tracer): replace class-based env access with functional helpers

[chetan9518]

Summary

This PR removes the legacy class-based EnvironmentVariablesService from the Tracer package and replaces it with functional getEnv helpers from @aws-lambda-powertools/commons.

Changes

• Removed EnvironmentVariablesService class
• Replaced all class-based env access with functional helpers (e.g. getEnv, getXRayTraceIdFromEnv)
• Removed EnvironmentVariablesService.test.ts (no longer needed)
• Confirmed all tests pass and builds succeed

Issue number: #4137

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[boring-cyborg]

Thanks a lot for your first contribution! Please check out our contributing guidelines and don't hesitate to ask whatever you need.
In the meantime, check out the #typescript channel on our Powertools for AWS Lambda Discord: Invite link

[dreamorosi]

Hi @chetan9518 thank you for opening this PR!

I'll review it soon, in the meantime could you please leave a comment on the linked issue, so that I can assign it to you?

GitHub doesn't allow me to assign issues if you haven't interacted with it first.

Thank you.

[dreamorosi]

Thank you again for the PR.

I've left a few comments but it's looking good.

Before pushing the next commit, could you please run npm run lint:fix -w packages/tracer from the root? I think some lines didn't get formatted correctly.

Also I noticed you left a comment under another issue, but not the one linked to this PR (#4137). Please leave a comment there so we can assign this to you - it really helps our tracking.

[dreamorosi]

Thank you for the PR, I made some small changes so I'll wait for another reviewer before merging it - but it's ok for me.

Thanks!

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[boring-cyborg]

Awesome work, congrats on your first merged pull request and thank you for helping improve everyone's experience!