docs: remove ambiguous options field from CREATE_ROOM message

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

docs/superpowers/specs/2026-04-02-web-games-platform-design.md

@@ -121,7 +121,7 @@ Extend the existing `/ws` endpoint (Bun native WebSocket in `server.ts`):
 | `JOIN_ROOM` | `{ roomId, as: "player" \| "spectator" }` |
 | `LEAVE_ROOM` | `{ roomId }` |
 | `GAME_ACTION` | `{ roomId, action: { type, ...data } }` |
-| `CREATE_ROOM` | `{ gameType, options? }` |
+| `CREATE_ROOM` | `{ gameType }` |
 | `PING` | (existing heartbeat) |
 
 ### Connection Model