fix(ui): green both lobby scores on a tie, mute a 0:0 board

The lobby tinted only the viewer's own number, and a tie counted as
"leading" — so an even score showed only the viewer's number green,
reading as if the viewer were ahead. A fresh 0:0 board did the same,
accenting the start of a game where nobody has scored.

scoreStanding is now per-seat: the viewer's seat stays green when
leading or tied and red when trailing; an opponent's seat greens only
when it ties the viewer for the lead, so an equal non-zero score paints
both numbers green. When the top score is 0 (nobody has moved) every
number is left muted, like a finished game.

ui/src/lib/lobbysort.ts

@@ -3,7 +3,7 @@
 // games — each ordered by last activity: your-turn oldest-first (the longest-neglected on
 // top), the other two newest-first.
 
-import type { GameView } from './model';
+import type { GameView, Seat } from './model';
 
 /** isMyTurn reports whether an active game's seat-to-move belongs to the caller. */
 export function isMyTurn(game: GameView, myId: string): boolean {
@@ -13,18 +13,26 @@ export function isMyTurn(game: GameView, myId: string): boolean {
 }
 
 /**
- * scoreStanding colours the viewer's own score on an in-progress game: 'win' when leading or
- * tied (green), 'lose' when trailing (red). It is null for any game that is not active (open or
- * finished — finished games show the result emoji instead) or where myId is not seated against
- * an opponent, so the lobby leaves those numbers in the muted default.
+ * scoreStanding colours a single seat's score on an in-progress game, viewed by myId. The
+ * viewer's own seat is 'win' (green) when it leads or ties for the lead and 'lose' (red) when it
+ * trails; any other seat is 'win' only when it ties the viewer for the lead, so an equal score
+ * paints both numbers green — otherwise an opponent's number keeps the muted default. It returns
+ * null (every number muted) for a game that is not active (open or finished — finished games show
+ * the result emoji instead), for a fresh 0:0 board where nobody has scored yet, and when myId is
+ * not seated against an opponent.
  */
-export function scoreStanding(game: GameView, myId: string): 'win' | 'lose' | null {
+export function scoreStanding(game: GameView, myId: string, seat: Seat): 'win' | 'lose' | null {
   if (game.status !== 'active') return null;
   const me = game.seats.find((s) => s.accountId === myId);
   if (!me) return null;
   const others = game.seats.filter((s) => s.accountId && s.accountId !== myId).map((s) => s.score);
   if (!others.length) return null;
-  return me.score >= Math.max(...others) ? 'win' : 'lose';
+  const top = Math.max(me.score, ...others);
+  if (top === 0) return null; // nobody has scored yet: leave the 0:0 board muted, like a finished game
+  const meLeads = me.score === top;
+  if (seat.accountId === myId) return meLeads ? 'win' : 'lose';
+  // Another seat greens only when it ties the leading viewer at the top — the equal-score case.
+  return meLeads && seat.score === top ? 'win' : null;
 }
 
 /**