feedback5 R1: startServer and main become wiring — PORT / HOST / TRUST_PROXY and the option picks go to http/config.js, the session stack and the /ws upgrade to http/websocket.js, the request listener and /healthz to http/routes.js (new), the security headers and the clientError 400 to http/common.js, the banner, signals and entry check to http/boot.js

Same order of construction, listeners and headers as before; a scripted fingerprint (export list, 51 HTTP requests'
status / header order / body hash, raw upgrade and malformed-request replies) and the process run (banner, port in
use, SIGINT) match the pre-split server exactly. test/version.test.js reads the banner and /healthz from their new
files; module headers describe each piece.

server/http/files.js

@@ -1,4 +1,4 @@
-// server/http/files.js — one file on disk → an HTTP response (moved from server/index.js):
+// server/http/files.js — one file on disk → an HTTP response (static.js and media.js decide which file):
 //     MIME types incl. .mjs/.js text/javascript, .skel application/octet-stream, .atlas text/plain;
 //     gzip for text-like types, .skel and uncompressed fonts when the client accepts it (small files are
 //     compressed once and cached in memory); strong ETag + Last-Modified with 304s; Cache-Control