The games-list status filter offered only active/finished; add 'open' (auto-match games awaiting an opponent) to the subnav and accept it in normalizeGameStatus. Render test covers the new filter link.
The real cause of 'Start game does not enter the game': encodeMatch gated the MatchResult game on matched (matched := m.Matched && m.Game != nil), so an open game awaiting an opponent (matched=false, game set) lost its game on the wire and the client had nothing to navigate into. Encode the game whenever m.Game is present; the backend's matched flag is authoritative. Regression test added (matched=false + game reaches the wire). The earlier codec fix guarded the same drop on the decode side.
Review fixes for open-game auto-match: decodeMatchResult dropped the game when matched=false (an open game awaiting an opponent), so the client never navigated into it - decode the game whenever present. The lobby grouped open games (status != 'active') into 'finished'; treat 'open' as in progress in groupGames/isMyTurn and resultBadge. The under-board status bar now reads "Opponent's turn" while the empty opponent seat is to move (instead of the searching placeholder). The New Game rule toggle is shown from the start when a Russian variant is available, so selecting a variant no longer shifts the layout.
Regression tests: codec (game decoded with matched=false), lobbysort + result (open is in progress), and the new-game e2e updated. UI-only; no backend or schema change.
Quick auto-match no longer waits on a separate screen: Enqueue opens a real game seating the caller with an empty opponent seat (new game status 'open') and the player enters it at once. A second human searching the same variant+rule joins that open game; otherwise a background reaper seats a robot after a 90s + random 0-90s wait, pushing a new in-app opponent_joined event that fills the opponent card and re-enables resign and chat in place.
Matchmaking state is now the open games in the database (the in-memory pool, lobby.poll and lobby.cancel are gone), serialised by a per-bucket advisory lock. While a game is open the starter may move on their turn, but resign, chat and nudge are refused; the lobby and opponent card show "searching for opponent".
Schema edited in the baseline (no prod data): 'open' status, nullable game_players.account_id for the empty seat, and a games.open_deadline_at stamp; jet code regenerated.
Ilia Denisov