publish.yml: add crates.io section to GitHub Release notes

[willwashburn]

The 2.0.0 release body (https://github.com/AgentWorkforce/burn/releases/tag/relayburn-v2.0.0) lists all 11 npm packages but doesn't mention the two crates.io publishes (`relayburn-sdk@2.0.0`, `relayburn-cli@2.0.0`) that ship in lockstep on every release.

Adds a `## Crates` section right after `## Packages`, with crate name, tag, and crates.io URL.

Future release bodies will look like:

## Packages

- \`relayburn@2.x.y\` (tag: \`relayburn-v2.x.y\`)
- ...

## Crates

- \`relayburn-sdk@2.x.y\` (tag: \`relayburn-sdk-v2.x.y\`) — https://crates.io/crates/relayburn-sdk/2.x.y
- \`relayburn-cli@2.x.y\` (tag: \`relayburn-cli-v2.x.y\`) — https://crates.io/crates/relayburn-cli/2.x.y

## Release Notes
...

The 2.0.0 release body has already shipped — happy to follow up with a `gh release edit relayburn-v2.0.0 --notes ...` to backfill it if you want, but that's a one-shot manual action and out of scope for this PR.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro Plus

Run ID: de99aedc-2251-4d29-9bda-c6c3e4864fe3

📥 Commits

Reviewing files that changed from the base of the PR and between d5a8116 and c270b39.

📒 Files selected for processing (1)

• .github/workflows/publish.yml

---

📝 Walkthrough

Walkthrough

Release notes generation in the publish workflow is extended with a dedicated "Crates" section. The script now adds entries for relayburn-sdk and relayburn-cli with their crates.io tags and versioned URLs immediately after the packages section.

Changes

Release Notes Enhancement

Layer / File(s)	Summary
Crates Listing in Release Notes .github/workflows/publish.yml	Release notes script adds a Crates section with relayburn-sdk and relayburn-cli entries, each including crates.io tags and direct version URLs.

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~3 minutes

Possibly related PRs

• AgentWorkforce/burn#362: Modifies .github/workflows/publish.yml's release/publish flow and release-note generation logic.
• AgentWorkforce/burn#353: Extends .github/workflows/publish.yml to add crates.io references in release notes/job summary.

Poem

🐰 A rabbit hops through workflows bright,
Adding crates to release notes with delight,
SDK and CLI now glow,
From crates.io's magical flow,
Each version tagged just right! 📦✨

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title directly describes the main change: adding a crates.io section to GitHub Release notes in the publish.yml workflow.
Description check	✅ Passed	The description provides clear context about why the change was needed, shows the expected output format, and explains the scope clearly.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch release-notes-crates

---

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