🧪 Add tests for wpAPI.updateMediaSEO function

[google-labs-jules]

🎯 What: The updateMediaSEO function in frontend/public/js/api.js was untested. This PR adds a conditional module export to make the file testable in Node.js (via Jest) while maintaining browser compatibility, and adds a dedicated test suite for this function.
📊 Coverage:

• Added frontend/tests/api.test.js.
• Mocked the wpAPI.request method and global alert.
• Tested the happy path: Verifying the correct endpoint (/wp/media/${id}), method (POST), and body format (JSON.stringify({ title, alt_text })) are used, and the expected response is returned.
• Tested the failure path: Verifying that request rejections are gracefully caught, alert is called with the specific error message format, and null is returned.
  ✨ Result: Test coverage is improved for the API helper methods, specifically covering the SEO update function's payload and error handling. Tests successfully run via npx jest in the frontend directory.

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PR created automatically by Jules for task 7102134340039936881 started by @instituto-ops

[google-labs-jules]

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