Add I18n locale strings for demo app (en only)

[myabc]

What are you trying to accomplish?

Copies a small subset of locale strings from @opf/openproject (en only) to the demo app for improved previews when running the lookbook locally and more accurate visual regression tests/screenshots.

Screenshots

Before

After

Integration

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?

@HDinger I've changed my mind a bit on this issue - I think the cost of having to maintain separate I18n strings in this repo is probably pretty small. It brings the advantage of better DX when working oninthe lookbook locally, as well as better screenshots.

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

[changeset-bot]

🦋 Changeset detected

Latest commit: 818d019

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

This PR includes changesets to release 1 package

Name	Type
@openproject/primer-view-components	Patch

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