ci(release): announce published token packages in Slack

[GarthDB]

Description

Adds two steps to the release job in .github/workflows/release.yml, after "Publish packages". When @adobe/spectrum-tokens or @adobe/spectrum-design-data is published, the workflow posts each package's version and GitHub release link to #spectrum-tokens through a Slack Workflow Builder webhook.

• The message is built from the publishedPackages output of the changesets action.
• Release links use the percent-encoded tag form (%40adobe/spectrum-tokens%40X.Y.Z).
• The steps skip when nothing relevant was published or when the SLACK_RELEASE_WEBHOOK_URL secret is missing.

Related Issue

None. There is no tracking issue for this change.

Motivation and Context

Token releases are currently announced by hand. Posting automatically keeps #spectrum-tokens current for every release without extra steps.

How Has This Been Tested?

• npx prettier --check .github/workflows/release.yml: passed.
• The SLACK_RELEASE_WEBHOOK_URL secret exists, and a manual curl POST to the same webhook posted to #spectrum-tokens.
• Not run: the new steps themselves. They only execute in the publish job on main, so the first real release is the first full test. actionlint was not available locally.

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• I have signed the Adobe Open Source CLA.
• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

[changeset-bot]

⚠️ No Changeset found

Latest commit: 42b65d3

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

This PR includes no changesets

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Click here to learn what changesets are, and how to add one.

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[github-actions]

Run report for 42b65d39

Total time: 2.3s | Comparison time: 2.1s | Estimated loss: 186.3ms (8.3% slower)

	Action	Time	Status	Info
⬛️	SetupProto(0.57.4)	0ms	Skipped
🟩	SyncWorkspace	6.5ms	Passed
🟩	SyncProject(root)	0.4ms	Passed
⬛️	SetupToolchain(node:20.17.0)	526.1ms	Skipped
⬛️	SetupToolchain(pnpm:10.17.1)	538.6ms	Skipped
⬛️	SetupToolchain(javascript)	0ms	Skipped
🟩	SetupEnvironment(javascript)	0.6ms	Passed
⬛️	InstallDependencies(javascript)	0.4ms	Skipped
🟩	RunTask(root:test)	1.2s	Passed

Changed files

.github/workflows/release.yml
scripts/legacy-consumers.allowlist.json

[github-actions]

🎨 Token Changes Report

Tokens Changed (0)

Original Branch: main

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[github-actions]

🧩 Component Schema Changes Report

No component schema changes detected.

This comment was automatically generated by the component schema diff tool. 🤖