telemetry(amazonq): sending metric data in onCodeGeneration

[siakmun-aws]

Problem

This is a part of the task to implement client side alarms in order to track success rate for the client.

Solution

• Emit metric data telemetry on success/failure.

---

• Treat all work as PUBLIC. Private feature/x branches will not be squash-merged at release time.
• Your code changes must meet the guidelines in CONTRIBUTING.md.

License: I confirm that my contribution is made under the terms of the Apache 2.0 license.

[github-actions]

• This pull request implements a feat or fix, so it must include a changelog entry (unless the fix is for an unreleased feature). Review the changelog guidelines.
  • Note: beta or "experiment" features that have active users should announce fixes in the changelog.
  • If this is not a feature or fix, use an appropriate type from the title guidelines. For example, telemetry-only changes should use the telemetry type.

[hayemaxi]

• This pull request implements a feat or fix, so it must include a changelog entry (unless the fix is for an unreleased feature). Review the changelog guidelines.

  • Note: beta or "experiment" features that have active users should announce fixes in the changelog.
  • If this is not a feature or fix, use an appropriate type from the title guidelines. For example, telemetry-only changes should use the telemetry type.

You should use telemetry(amazonq) instead of feat in the commit and PR title to avoid this.

[nkomonen-amazon]

I'm not sure if these designs are final. But does it makes to just send a single metric instead of start/end? This would save some work on the server side

[siakmun-aws]

The purpose of this design was to get the success rate by calculating end versus start, so we do need two separate metrics. Also, start can potentially fail too.