fix: return fightId from ranked queue on duplicate join, fix calculateTier call

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

server/src/engine/lifecycle.test.ts

@@ -536,7 +536,7 @@ describe('fight lifecycle', () => {
 
       // Elo + tier calculation
       calculateElo(eloA, eloB)
-      calculateTier(eloA, f % 50, f % 20)
+      calculateTier(eloA, f % 50)
     }
 
     const elapsed = performance.now() - start

server/src/engine/ranked-queue.ts

@@ -1,7 +1,7 @@
 import { logger } from '../lib/logger.js'
 import { db, schema } from '../db/index.js'
 import { eq, sql } from 'drizzle-orm'
-import { runFightAsync, isInFight } from './orchestrator.js'
+import { runFightAsync, isInFight, getActiveFightId } from './orchestrator.js'
 import { checkPaymentStatus, refundEntry, consumePaymentForQueue, linkPaymentsToFight, releasePayment } from './payments.js'
 
 interface RankedQueueEntry {
@@ -61,10 +61,12 @@ export async function joinRankedQueue(botId: string, paymentId: string): Promise
     throw new Error(`Cooldown active. Wait ${waitSec}s.`)
   }
 
-  // Check if already in a fight
+  // Check if already in a fight — return fightId so frontend can redirect
   if (isInFight(botId)) {
     releasePayment(paymentId)
-    throw new Error('Bot is already in a fight.')
+    const err = new Error('Bot is already in a fight.')
+    ;(err as any).fightId = getActiveFightId(botId)
+    throw err
   }
 
   // Load bot