v0.8.4 — the multiplayer transport: server and browser

The second release from the audit. Every fault here was invisible in solitaire, and four of
the five server faults were in the one file no test had ever stood up; `http.ts` now has an
end-to-end suite on a real port. CHANGELOG has the reasoning.

SERVER. Leaving a lobby freed the chair and kept the token, so a leaver could stream and
move for whoever took the seat next — revoked now, in memory and on disk. The browser
numbered intents from 1 per page load while the server remembered the seat's last number,
so the first move after a reload was swallowed as a resend — the connect push carries the
count and the client continues from it. Nothing serialised moves within a game and every
write shared one `.tmp` name, so two moves at once tore `game.json` (measured: 6 of 200),
and the boot's bare `JSON.parse` then took every game down — per-path write queues, a
per-game move queue, and a boot that skips one bad file. An error after the SSE head was
sent crashed the process. Bodies were unbounded before any secret check.

BROWSER. A double-click did the thing twice: one submit in flight at a time. A failed
submit is `false`, not an unhandled rejection. The documentation renderer flattened nested
bullets into a literal "- " mid-sentence on the published home-deck page. The make-up panel
promised cars the engine refuses; it asks `acceptsCar` now.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FrCWubm9GAftYCm2hWdKwK

src/server/index.ts

@@ -61,8 +61,22 @@ for (const entry of index) {
   }
 
   const loaded = await loadGame(gameDir(dataDir, entry.gameId));
+  if (!loaded.found && loaded.corrupt) {
+    // One unreadable file is one game lost, not every game (v0.8.4) — see `loadGame`.
+    console.error(`Skipping ${entry.gameId} (${entry.gameCode}): game.json is unreadable — ${loaded.corrupt}. The file is left untouched.`);
+    continue;
+  }
   if (loaded.found) {
-    const resumed = tryResumeSession(loaded.saved);
+    let resumed: ReturnType<typeof tryResumeSession>;
+    try {
+      resumed = tryResumeSession(loaded.saved);
+    } catch (err) {
+      // A save that parses but is not the shape the replay expects (no config, a history entry
+      // that is not an intent) throws inside the engine rather than being refused. Same answer:
+      // this game, not the server.
+      console.error(`Skipping ${entry.gameId} (${entry.gameCode}): the save could not be replayed — ${err instanceof Error ? err.message : String(err)}. The file is left untouched.`);
+      continue;
+    }
     if (resumed.ok) {
       initialGames.set(entry.gameId, resumed.session);
       console.log(`Resumed ${entry.gameId} (${entry.gameCode}) — ${loaded.saved.history.length} intents replayed.`);