Publish an OpenSearch description so browsers can search the catalog #241

Summary

Browsers cannot add the catalog as a search engine because the site publishes no OpenSearch description. The page already reads its search state from the query string, so this needs no client changes.

Where

• site/build.mjs:648-733 (output list has no opensearch.xml)
• site/public/index.html (no <link rel="search">)
• site/public/app.js:75 (readState(location.search, …))

Proposal

Have the build write opensearch.xml (ShortName, Description, a Url template built from config.site.siteUrl with the search query parameter set to {searchTerms}, favicon) and add <link rel="search" type="application/opensearchdescription+xml" title="…" href="opensearch.xml"> to index.html.

Who benefits

Frequent visitors can type a keyword plus a query in the address bar and land in a filtered view.

Open questions

Confirm the exact query parameter name that readState uses before writing the template.

Acceptance criteria

• opensearch.xml is built and linked from the homepage
• adding it in a browser and searching opens the filtered catalog

Getting started

• Relevant files: site/build.mjs, site/public/index.html, site/lib/search.mjs
• How to run: npm run build && npm run serve

_{Filed by repo-audit/full-audit at d6e56a8. Severity: low. Effort: S. audit-key: enhancement|site/build.mjs|opensearch}