v0.7.7 — two releases shipped to a browser that never received them

buildStamp()'s no-git fallback was the literal "nogit", and the .s9pk
Dockerfile copies the tree in without .git — so git rev-parse fails on
every packaged build. That string is also the cache-bust key every
module URL carries, so v0.7.4, v0.7.5 and v0.7.6 all published
./web/main.js?v=nogit, byte-identical, and returning browsers refetched
nothing. v0.7.5's setup screen and v0.7.6's door fix were both correct
and neither arrived.

The fallback is now the package version plus the build timestamp, always
distinct. And serveStatic sent no Cache-Control at all, which is the
other half — a cached play.html pins a player to the whole build it
names. A request carrying ?v= is now immutable for a year; everything
else is no-cache. ?v= rather than "not HTML" because build-web.ts tags
the modules and nothing else.

Neither half is sufficient alone.

864 tests pass, two new.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AdG46Ja2PEDBkpqiDazMoX

scripts/build-web.ts

@@ -60,7 +60,21 @@ execFileSync(
  */
 function buildStamp(): string {
   const pkg = JSON.parse(readFileSync(join(root, 'package.json'), 'utf8')) as { version: string };
-  let git = 'nogit';
+  /**
+   * THE FALLBACK HAS TO BE UNIQUE PER BUILD, because this string is also the cache-bust key.
+   *
+   * It used to be the literal `nogit`, which is exactly what the `.s9pk` build produces — the
+   * Dockerfile copies the working tree in without `.git`, so `git rev-parse` fails there every time.
+   * Every packaged release therefore published `?v=nogit`, byte-identical to the release before it,
+   * and a returning player's browser had no reason to refetch a single module. v0.7.5's setup screen
+   * and v0.7.6's fix to it both shipped correctly to `phoenix.local` and neither reached the browser
+   * that asked for them (Jesse, twice, 2026-08-29 — "setup did not work").
+   *
+   * The version plus the build's own timestamp is always distinct, needs nothing from the
+   * environment, and stays honest: two builds of the same commit ARE two deploys, and a cache key
+   * that says so costs one refetch, while one that lies costs a release nobody receives.
+   */
+  let git = `${pkg.version}-${Date.now().toString(36)}`;
   try {
     const sha = execFileSync('git', ['rev-parse', '--short', 'HEAD'], { cwd: root })
       .toString()