chore: command orchestration

[TarunAdobe]

Description

• Added build-, test-, start-, and lint- root scripts so first- and second-gen workspaces can be orchestrated together.
• Introduced a prebuild wireit target in first-gen/package.json that triggers the second-gen core build before the existing build pipeline.
• Renamed the second-gen workspace to @adobe/swc and updated yarn.lock to reflect the new package name.

Motivation and context

• Make the root package the single entry point for common dev workflows that span both generations of Spectrum Web Components.
• Ensure first-gen builds automatically compile second-gen core artifacts to keep shared output in sync.

Related issue(s)

• fixes [Issue Number]

Screenshots (if appropriate)

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Author's checklist

• I have read the CONTRIBUTING and PULL_REQUESTS documents.
• I have reviewed at the Accessibility Practices for this feature, see: Aria Practices
• I have added automated tests to cover my changes.
• I have included a well-written changeset if my change needs to be published.
• I have included updated documentation if my change required it.

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Reviewer's checklist

• Includes a Github Issue with appropriate flag or Jira ticket number without a link
• Includes thoughtfully written changeset if changes suggested include patch, minor, or major features
• Automated tests cover all use cases and follow best practices for writing
• Validated on all supported browsers
• All VRTs are approved before the author can update Golden Hash

Manual review test cases

• Descriptive Test Statement

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  2. Do this action
  3. Expect this result

• Descriptive Test Statement

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  2. Do this action
  3. Expect this result

Device review

• Did it pass in Desktop?
• Did it pass in (emulated) Mobile?
• Did it pass in (emulated) iPad?

[changeset-bot]

⚠️ No Changeset found

Latest commit: ffa43cc

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[github-actions]

📚 Branch Preview

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🔍 Visual Regression Test Results

When a visual regression test fails (or has previously failed while working on this branch), its results can be found in the following URLs:

• Spectrum | Light | Medium | LTR
• Spectrum | Dark | Large | RTL
• Express | Light | Medium | LTR
• Express | Dark | Large | RTL
• Spectrum-two | Light | Medium | LTR
• Spectrum-two | Dark | Large | RTL
• High Contrast Mode | Medium | LTR

Deployed to Azure Blob Storage: pr-5791

If the changes are expected, update the current_golden_images_cache hash in the circleci config to accept the new images. Instructions are included in that file.
If the changes are unexpected, you can investigate the cause of the differences and update the code accordingly.

[github-actions]

Tachometer results

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