fix(session): reset lobby when player leaves finished match

docs/PLAYER_UI.md

@@ -66,6 +66,12 @@ closing this presentation-only menu never sends a command or changes server
 state. Escape and outside activation dismiss it; player actions also close it
 before opening their existing destination.
 
+Authenticated sessions also see `Выйти из игры`. Its confirmation states that
+a player exit from any non-waiting phase, including the result screen, returns
+the remaining participants to the waiting lobby; observer exits and waiting
+lobby player exits release only the departing browser's place. The browser
+removes its token only after the correlated server acknowledgement.
+
 The header response indicator takes at most one heartbeat sample every five
 seconds, holds one in-flight request, and uses a five-sample median. Good is
 at most 150 ms, delayed is 151--500 ms, and slow is above 500 ms. Hysteresis

docs/PROTOCOL.md

@@ -40,7 +40,8 @@ is only echoed for correlation; it grants no authority.
   players must be connected. Sessions are preserved while a new authoritative
   maze and game state are created.
 - `leave`: `{}`. Revokes only the authenticated sending session. A player
-  leaving an unfinished match cancels it for all participants; observer and
+  leaving any non-waiting match phase, including a finished result, cancels
+  that match and returns remaining sessions to the waiting lobby; observer and
   waiting-lobby departures release only that session.
 - `heartbeat`: `{}` after a session has been joined or restored.
 

docs/UI_STYLE.md

@@ -107,9 +107,9 @@ are not MVP requirements.
   safe areas, closes on outside activation or Escape, and never contains
   primary game, lobby, observer, or result actions.
 - The settings popover shows `Выйти из игры` only for an authenticated session.
-  It opens a confirmation modal; an unfinished player match warns that it ends
-  for everyone, while observer and lobby departures explain that only this
-  browser's place is released.
+  It opens a confirmation modal; a player match, including a finished result,
+  warns that it returns everyone to the waiting lobby, while observer and
+  waiting-lobby departures explain that only this browser's place is released.
 - A compact response indicator between the connection state and gear shows a
   rounded total response time or an explicit unknown, stale, or offline state.
   Its accessible description and settings details expose `Отклик`, `Связь`,