Forfeit = 2x coin loss + 0 XP (no kot); end-of-game roster + add friend

Forfeit penalty reworked (client + server gamification, in sync):
- Surrendering team loses DOUBLE the entry coins; winner takes the stake.
- Forfeiter earns NO XP. No kot is applied or mentioned anymore.
- MatchSummary/Dto carry a `forfeit` flag; GameRoom.FinalizeForfeit →
  ApplyRewardsAsync(team) with Forfeit=true (dropped the kot path).
- Forfeit confirm dialogs now alert the real penalty (double coins, no XP).

End-of-game roster: SeatPlayerDto/ServerSeatPlayer + game-store SeatPlayer gain
userId/isBot. New <MatchPlayersList> lists everyone at the table on the final
screen (PostMatchRewardsModal + AI MatchOverlay) with a tactile "Add" button to
send a friend request to real (non-bot, non-self) players ("Sent" after).

Verified: tsc + sim + dotnet + next build clean; stack rebuilt :1500/:1505.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

scripts/sim.ts

@@ -126,6 +126,7 @@ for (let i = 0; i < M; i++) {
     shutout: won && i % 8 === 0,
     hakemRounds: i % 3,
     roundsWon: won ? 7 : i % 7,
+    forfeit: false,
   };
   const before = profile;
   const { profile: after, reward } = applyMatchResult(before, summary, 1000);
@@ -152,7 +153,7 @@ for (let i = 0; i < M; i++) {
 {
   const r = applyMatchResult(baseProfile(), {
     ranked: false, stake: 0, won: true, kotFor: false, kotAgainst: false,
-    tricksWon: 7, rounds: 7, trump: null, shutout: false, hakemRounds: 0, roundsWon: 7,
+    tricksWon: 7, rounds: 7, trump: null, shutout: false, hakemRounds: 0, roundsWon: 7, forfeit: false,
   }, 1000);
   assert(r.reward.ratingDelta === 0, "casual match must not change rating");
 }