feat: wire bet settlement into fight finalization

Lock bets when fight goes live, settle all bets atomically when fight
ends. Winners get Cashu payout tokens, losers forfeit. Draws refund
all bets. Settlement results persisted to bets table.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

server/src/engine/orchestrator.ts

@@ -10,6 +10,7 @@ import { generateMockBotResponse, isClassicBot, generateClassicBotResponse } fro
 import { setCooldown } from './queue.js'
 import { isHumanPlayer, waitForHumanResponse } from './human-responses.js'
 import { payWinner, refundEntry, ENTRY_FEE_SATS } from './payments.js'
+import { settleBets, lockBets } from './betting.js'
 
 interface BotRecord {
   id: string
@@ -295,6 +296,9 @@ async function createFightRecord(botA: BotRecord, botB: BotRecord, arena: Arena,
     startedAt: now,
     createdAt: now,
   })
+  // Lock bets when fight starts
+  lockBets(fightId)
+
   emit(fightId, 'fight_start', {
     botA: { id: botA.id, name: botA.name, elo: botA.eloRating },
     botB: { id: botB.id, name: botB.name, elo: botB.eloRating },
@@ -506,6 +510,21 @@ async function executeFightRounds(fightId: string, botA: BotRecord, botB: BotRec
     potSats: mode === 'ranked' ? 42 : 0,
   })
 
+  // Settle bets
+  try {
+    const settlements = await settleBets(fightId, winnerId)
+    for (const s of settlements) {
+      db.update(schema.bets).set({
+        status: s.won ? 'won' : winnerId ? 'lost' : 'refunded',
+        payoutSats: s.payoutSats,
+        payoutToken: s.payoutToken,
+        settledAt: new Date().toISOString(),
+      }).where(eq(schema.bets.id, s.betId)).run()
+    }
+  } catch (err) {
+    console.error(`[betting] settlement failed for fight ${fightId}:`, err)
+  }
+
   // Ranked fight payout
   if (mode === 'ranked') {
     // Dev mode: always pay the human bot (not mock), regardless of win/loss