[SelectPanel] Improve messages API

[camertron]

What are you trying to accomplish?

Now that we've decided on a messages API for the PRC SelectPanel, I thought it was time to dust off this old PR and implement the new API for PVC as well.

Screenshots

There should be no perceivable visual changes.

Integration

Yes. We will need to migrate existing usages of the no_results_label argument and the error_content and preload_ error_content slots. no_results_label should be straightforward to identify using primer-query, and a quick search should show us where with_error_content and with_preload_error_content are being used.

List the issues that this change affects.

Closes # (type the GitHub issue number after #)

Risk Assessment

• Low risk the change is small, highly observable, and easily rolled back.
• Medium risk changes that are isolated, reduced in scope or could impact few users. The change will not impact library availability.
• High risk changes are those that could impact customers and SLOs, low or no test coverage, low observability, or slow to rollback.

What approach did you choose and why?

Anything you want to highlight for special attention from reviewers?

Accessibility

• Fixes axe scan violation - This change fixes an existing axe scan violation.
• No new axe scan violation - This change does not introduce any new axe scan violations.
• New axe violation - This change introduces a new axe scan violation. Please describe why the violation cannot be resolved below.

Merge checklist

• Added/updated tests
• Added/updated documentation
• Added/updated previews (Lookbook)
• Tested in Chrome
• Tested in Firefox
• Tested in Safari
• Tested in Edge

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[changeset-bot]

🦋 Changeset detected

Latest commit: 3611153

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@primer/view-components	Minor

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[github-actions]

⚠️ Visual differences found

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