fix: Correct PnL calculation to show net profit instead of gross payout

- GameServer.ts: Calculate netProfit = grossPayout - betAmount and send as 'net'
  instead of sending gross payout labeled as net
- BlackjackGame.tsx: Fix PnL calculations to use net profit correctly
  - Hand win/blackjack now shows net profit (payout minus bet)
  - Lose correctly shows negative bet amount
  - Round result banner displays roundNet (net profit) with appropriate colors
- Remove dead code (myPnl variable that was calculated but never used)
- Update color coding: green for profit, red for loss, blue for zero balance

api/src/games/GameServer.ts

@@ -97,15 +97,16 @@ export class GameServer {
 
             for (const [playerId, multiplier] of Object.entries(roundPayouts)) {
                 if (multiplier <= 0) continue;
-                const amount = Math.floor(betAmount * multiplier);
+                const grossPayout = Math.floor(betAmount * multiplier);
+                const netProfit = grossPayout - betAmount; // Calculate net profit (gross payout minus original bet)
                 try {
                     await economyService.modifyUserBalance(
                         playerId,
-                        BigInt(amount),
+                        BigInt(grossPayout),
                         TransactionType.GAME_WIN,
                         `${gameName} round payout (room ${roomId.slice(0, 8)})`,
                     );
-                    payoutDetails[playerId] = { net: amount };
+                    payoutDetails[playerId] = { net: netProfit };
                 } catch (err) {
                     logger.error("web", `Round payout failed for ${playerId} in room ${roomId}: ${err}`);
                 }

panel/src/games/blackjack/BlackjackGame.tsx

@@ -211,13 +211,13 @@ function Seat({ seat, playerName, isMe, isActivePlayer, activeHandIdx, betAmount
     const hasHands = seat.hands.length > 0;
     const compact = seat.hands.length > 2;
 
-    // Calculate current round PnL for the display
+    // Calculate current round PnL for the display (only needed before results are shown)
     const currentRoundPnl = seat.hands.reduce((sum, h) => {
         if (!h.result) return sum; // Not yet resolved
         const handWin = h.bet * betAmount;
-        if (h.result === "win" || h.result === "blackjack") return sum + handWin;
+        if (h.result === "win" || h.result === "blackjack") return sum + (handWin - betAmount); // Net profit
-        if (h.result === "push") return sum; // Push returns bet
+        if (h.result === "push") return sum; // Push returns bet, so net is 0
-        return sum - handWin; // Lose
+        return sum - betAmount; // Lose loses the bet amount
     }, 0);
     const totalPnl = seat.cumulativePnl + currentRoundPnl;
 
@@ -364,11 +364,11 @@ function RoundResultBanner({ roundNumber, roundResult, myPlayerId, betAmount, my
         <div className="flex items-center justify-center gap-3 bg-black/30 rounded-xl px-4 py-2">
             <span className="text-xs text-white/50">Round {roundNumber}</span>
             <div className="flex items-center gap-2">
-                {myPayout && betAmount > 0 && (
+                {betAmount > 0 && (
                     <span className={`text-xs font-semibold ${
-                        myPayout.net > betAmount ? "text-emerald-400" : myPayout.net === betAmount ? "text-blue-400" : "text-white/60"
+                        roundNet > 0 ? "text-emerald-400" : roundNet < 0 ? "text-red-400" : "text-blue-300"
                     }`}>
-                        Round: {myPayout.net > 0 ? "+" : ""}{myPayout.net} AU
+                        Round: {roundNet > 0 ? "+" : ""}{roundNet} AU
                     </span>
                 )}
                 <div className="w-px h-4 bg-white/20" />
@@ -398,16 +398,6 @@ export function BlackjackGame({ state, myPlayerId, isSpectator, onAction, player
     }, [players]);
 
     const mySeat = view.seats[myPlayerId];
-    const myBetPlaced = mySeat?.hasBet ?? false;
-
-    // Calculate current balance (if betting) or just track profit/loss
-    const balance = betAmount > 0 && mySeat?.hands.length === 0
-        ? 0 // Not yet bet for this round
-        : mySeat?.hands.reduce((sum, h) => sum + (h.result === "win" || h.result === "blackjack"
-            ? h.bet * betAmount
-            : h.result === "push" ? h.bet * betAmount
-            : 0), 0) - (myBetPlaced ? mySeat.hands.reduce((sum, h) => sum + h.bet * betAmount, 0) : 0);
-    const myPnl = (mySeat?.cumulativePnl ?? 0) + balance;
 
     // Determine who can sit (spectators during betting phase)
     const canSitDown = isSpectator && isBetting && view.turnOrder.length < 6;