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.test.ts

@@ -126,22 +126,42 @@ describe('scoreStanding', () => {
       { ...seat(1, 'opp'), score: oppScore },
     ],
   });
+  const at = (g: GameView, accountId: string): Seat => g.seats.find((s) => s.accountId === accountId)!;
 
-  it('greens a leading or tied active game, reds a losing one', () => {
-    expect(scoreStanding(withScores('active', 30, 10), ME)).toBe('win');
-    expect(scoreStanding(withScores('active', 10, 10), ME)).toBe('win'); // a tie counts as green
-    expect(scoreStanding(withScores('active', 5, 10), ME)).toBe('lose');
+  it('greens the leading viewer and reds a trailing one; the opponent stays muted', () => {
+    const lead = withScores('active', 30, 10);
+    expect(scoreStanding(lead, ME, at(lead, ME))).toBe('win');
+    expect(scoreStanding(lead, ME, at(lead, 'opp'))).toBeNull(); // a trailing opponent is not coloured
+
+    const behind = withScores('active', 5, 10);
+    expect(scoreStanding(behind, ME, at(behind, ME))).toBe('lose');
+    expect(scoreStanding(behind, ME, at(behind, 'opp'))).toBeNull(); // a leading opponent is not coloured
+  });
+
+  it('greens both seats on an equal non-zero score', () => {
+    const tie = withScores('active', 10, 10);
+    expect(scoreStanding(tie, ME, at(tie, ME))).toBe('win');
+    expect(scoreStanding(tie, ME, at(tie, 'opp'))).toBe('win');
+  });
+
+  it('leaves a fresh 0:0 board muted (nobody has scored yet)', () => {
+    const fresh = withScores('active', 0, 0);
+    expect(scoreStanding(fresh, ME, at(fresh, ME))).toBeNull();
+    expect(scoreStanding(fresh, ME, at(fresh, 'opp'))).toBeNull();
   });
 
   it('is null for any non-active game (open or finished)', () => {
-    expect(scoreStanding(withScores('finished', 30, 10), ME)).toBeNull();
-    expect(scoreStanding(withScores('open', 0, 0), ME)).toBeNull();
+    const fin = withScores('finished', 30, 10);
+    expect(scoreStanding(fin, ME, at(fin, ME))).toBeNull();
+    const op = withScores('open', 0, 0);
+    expect(scoreStanding(op, ME, at(op, ME))).toBeNull();
   });
 
   it('is null when the viewer is not seated or has no opponent', () => {
-    expect(scoreStanding(withScores('active', 30, 10), 'stranger')).toBeNull();
+    const g = withScores('active', 30, 10);
+    expect(scoreStanding(g, 'stranger', at(g, ME))).toBeNull();
     const solo: GameView = { ...game('g', 'active', 0, 0), seats: [{ ...seat(0, ME), score: 9 }] };
-    expect(scoreStanding(solo, ME)).toBeNull();
+    expect(scoreStanding(solo, ME, solo.seats[0])).toBeNull();
   });
 
   it('compares against the strongest opponent in a multiplayer game', () => {
@@ -151,10 +171,26 @@ describe('scoreStanding', () => {
       seats: [
         { ...seat(0, ME), score: 40 },
         { ...seat(1, 'a'), score: 35 },
-        { ...seat(2, 'b'), score: 50 }, // b is ahead -> losing
+        { ...seat(2, 'b'), score: 50 }, // b is ahead -> the viewer is losing
       ],
     };
-    expect(scoreStanding(g3, ME)).toBe('lose');
+    expect(scoreStanding(g3, ME, at(g3, ME))).toBe('lose');
+    expect(scoreStanding(g3, ME, at(g3, 'b'))).toBeNull(); // a leading opponent is not coloured
+  });
+
+  it('greens every seat tied with the viewer for the lead in a multiplayer game', () => {
+    const g3: GameView = {
+      ...game('g', 'active', 0, 0),
+      players: 3,
+      seats: [
+        { ...seat(0, ME), score: 40 },
+        { ...seat(1, 'a'), score: 40 }, // tied with the viewer for the lead -> green
+        { ...seat(2, 'b'), score: 20 }, // trailing -> muted
+      ],
+    };
+    expect(scoreStanding(g3, ME, at(g3, ME))).toBe('win');
+    expect(scoreStanding(g3, ME, at(g3, 'a'))).toBe('win');
+    expect(scoreStanding(g3, ME, at(g3, 'b'))).toBeNull();
   });
 });