[WIP] Fix static file serving problems causing CI test failures

[Copilot]

Thanks for asking me to work on this. I will get started on it and keep this PR's description up to date as I form a plan and make progress.

Original prompt

some tests are failing in the CI because of static file serving problems:
AssertionError: JavaScript errors found: [{'level': 'SEVERE', 'message': 'http://localhost:59183/static/vendor/tailwind.css - Failed to load resource: the server responded with a status of 404 (NOT FOUND)', 'source': 'network', 'timestamp': 1767908331764}, {'level': 'SEVERE', 'message': 'http://localhost:59183/static/vendor/fontawesome.min.css - Failed to load resource: the server responded with a status of 404 (NOT FOUND)', 'source': 'network', 'timestamp': 1767908331764}, {'level': 'SEVERE', 'message': 'http://localhost:59183/static/vendor/katex.min.css - Failed to load resource: the server responded with a status of 404 (NOT FOUND)', 'source': 'network', 'timestamp': 1767908331768}, {'level': 'SEVERE', 'message': 'http://localhost:59183/static/vendor/katex.min.js - Failed to load resource: the server responded with a status of 404 (NOT FOUND)', 'source': 'network', 'timestamp': 1767908331769}, {'level': 'SEVERE', 'message': 'http://localhost:59183/static/vendor/marked.min.js - Failed to load resource: the server responded with a status of 404 (NOT FOUND)', 'source': 'network', 'timestamp': 1767908331769}, {'level': 'SEVERE', 'message': 'http://localhost:59183/static/vendor/marked-katex-extension.min.js - Failed to load resource: the server responded with a status of 404 (NOT FOUND)', 'source': 'network', 'timestamp': 1767908331772}]

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