The api.js library-list fix from the previous commit never reached the browser because nginx served all .js with `Cache-Control: public, immutable; max-age=31536000`. The HTML referenced api.js with no version query, so the browser kept its year-cached buggy copy.
* nginx.conf: drop .js from the immutable long-cache block, add a no-cache must-revalidate block so future redeploys are picked up immediately.
* All HTML files: tag api.js refs with ?v=4 so already-running browsers fetch the new version on next page load.
nginx resolves upstream hostnames at config load time, which fails when
sibling containers haven't registered with the Docker DNS yet. Using
resolver 127.0.0.11 with set $upstream defers resolution to request
time, preventing the "host not found in upstream" startup crash.
