New spa/serve-spa.ts: @fastify/static with wildcard:false plus a GET /*
catch-all that returns index.html for non-backend paths and a JSON 404
for unknown /api, /mcp, /socket.io paths. WEB_DIST_DIR unset disables
serving (dev uses the Vite dev server, which proxies to the gateway);
set but invalid fails loud at boot.
A wildcard route, not setNotFoundHandler: Nest installs its own
not-found handler at init and Fastify allows only one. find-my-way
matches most-specific-first, so declared routes win over the catch-all.
Cache semantics stay the library default (max-age=0 + ETag
revalidation); immutable hashed-asset caching is deferred to P6.
gateway.Dockerfile builds the web bundle and ships it at /app/web-dist
with WEB_DIST_DIR set.
fred
385b2b6886