fix(tracer): pass args of decorated method as they are

[dreamorosi]

Summary

Changes

Please provide a summary of what's being changed

This PR updates the internal implementation of the captureLambdaHandler class method decorator in Tracer so that it forwards the args of the decorated handler method as they appear at runtime rather than destructuring them and forcing the third parameter (callback) to be undefined.

Its presence, even when not defined, caused the runtime to interpret the handler as using callback style, which in turn caused deprecation warnings to show up.

Please add the issue number below, if no issue is present the PR might get blocked and not be reviewed

Issue number: closes #4306

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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

[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

[dreamorosi]

@sdangol can you please review the implementation of all the other decorators in the codebase and see if they need the same change? If needed, you can use the triaging runbook and deploy a functions to verify whether decorating causes a warning:

import type { Callback } from 'aws-lambda';

class Handler {
  // insert decorator here - should not cause a warning
  handler(event: unknown, context: unknown) {
    return {
      statusCode: 200,
      body: JSON.stringify({ message: 'Hello from Lambda!' }),
    };
  }
}

const lambda = new Handler();
export const handler = lambda.handler.bind(lambda);

If you find any, can you open a group issue to apply the same fix and link it back in #4312?

[boring-cyborg]

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