Slack perf release

[jperez999]

Description

Implemented the Slack publishing step in .github/workflows/perform-release.yml:377.

• Saves the generated announcement as a JSON-safe Slack payload.
• Adds the final conditional “Publish announcement to Slack” step.
• Posts via secrets.SLACK_WEBHOOK with retry and HTTP failure handling.

Validation: YAML parse and git diff --check passed. No docs update was needed; this is an internal release-workflow secret.

Checklist

• I am familiar with the Contributing Guidelines.
• New or existing tests cover these changes.
• The documentation is up to date with these changes.

[copy-pr-bot]

This pull request requires additional validation before any workflows can run on NVIDIA's runners.

Pull request vetters can view their responsibilities here.

Contributors can view more details about this message here.

[greptile-apps]

Greptile Summary

The PR adds Slack publication to the release workflow and addresses the previously reported multiline, dry-run, and duplicate-retry paths. However, the revised request now fails permanently on the first transient HTTP rejection.

• Serializes the multiline announcement into one JSON payload.
• Prevents dry-run executions from invoking the webhook.
• Posts the payload through the configured Slack webhook.

Confidence Score: 4/5

The PR is not yet safe to merge because a transient Slack HTTP rejection immediately fails the release notification instead of receiving a safe retry.

The webhook command makes only one attempt, so a temporary 429 or server error leaves the release announcement unpublished and the workflow failed.

Files Needing Attention: .github/workflows/perform-release.yml

Important Files Changed

Filename	Overview
.github/workflows/perform-release.yml	Adds guarded Slack publication and correct JSON serialization, but removes retries even for transient responses that definitively rejected the request.

Prompt To Fix All With AI

### Issue 1
.github/workflows/perform-release.yml:514
**Transient rejections drop announcements**

When Slack returns a transient response that definitively rejects the request, such as HTTP 429 or 5xx, this single-attempt `curl` command fails the publication step without retrying, leaving the release announcement unpublished even though retrying that response is safe.

---

For each issue above, determine whether it is valid and should be fixed. If so, fix it directly.

_{Reviews (3): Last reviewed commit: "Merge branch 'main' into slack-perf-rele..." | Re-trigger Greptile}

[greptile-apps]

Transient rejections drop announcements

When Slack returns a transient response that definitively rejects the request, such as HTTP 429 or 5xx, this single-attempt curl command fails the publication step without retrying, leaving the release announcement unpublished even though retrying that response is safe.

Prompt To Fix With AI

This is a comment left during a code review.
Path: .github/workflows/perform-release.yml
Line: 514

Comment:
**Transient rejections drop announcements**

When Slack returns a transient response that definitively rejects the request, such as HTTP 429 or 5xx, this single-attempt `curl` command fails the publication step without retrying, leaving the release announcement unpublished even though retrying that response is safe.

---

For each issue above, determine whether it is valid and should be fixed. If so, fix it directly.