实现账号绑定、持久登录与跨设备对局恢复

docs/META.md

@@ -175,6 +175,11 @@ otherwise every "之后 / 后续的每场作战" card — e.g. 教鞭's 法术
 A `choice:<effectId>` registry handler overrides the default application (§2.4).
 
 ### 1.3 Disconnects, AI takeover
+* Account-required fork (§31.13, [skland.md](skland.md) §5): the selected UID + region can resume the same retained
+  seat on another device after explicit authenticated entry. Login/lookup alone does not replace a socket. The
+  transport rotates its token on successful attachment, while the match and its private state stay the same.
+  Account recovery does not extend the deadlines below or survive a server restart; an expired role's old seat goes
+  through the normal lobby onExpire/onLeave cleanup before a new session can reuse its stable playerId.
 * Local multi-window recovery (#431, DESIGN §28.27) sends optional `hello.noReplace` for a tentative shared token,
   and `hello.claimAt` for a previously welcomed token. Before binding a different socket, the server rejects a
   connected seat when no replacement was allowed or the request has a later stamp than the attached holder