feat: computed achievement system — 20 achievements derived from bot stats

Achievements computed on-the-fly from existing stats + fight history:
win milestones, streaks, tiers, ELO, perfect/KO wins, resilience, activity.
Wired into /api/bots/:name/stats endpoint.

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

server/src/routes/bots.ts

@@ -4,6 +4,7 @@ import { createHash, randomBytes } from 'crypto'
 import { db, schema } from '../db/index.js'
 import { eq, or, desc, sql } from 'drizzle-orm'
 import { TIER_NAMES, TIER_COLORS } from '../engine/scoring.js'
+import { computeAchievements } from '../engine/achievements.js'
 import { isAllowedWebhookUrl } from '../engine/orchestrator.js'
 import { testWebhook } from '../engine/webhook-test.js'
 import { rateLimit } from '../middleware/rate-limit.js'
@@ -180,15 +181,27 @@ botsRouter.get('/:name/stats', async (c) => {
   allBots.sort((a, b) => b.eloRating - a.eloRating)
   const rank = allBots.findIndex(b => b.id === bot.id) + 1
 
-  // Recent fights (last 10)
-  const fights = await db.select()
-    .from(schema.fights)
+  // All fights for achievements
+  const allFights = await db.select({
+    winnerId: schema.fights.winnerId,
+    totalRounds: schema.fights.totalRounds,
+    botAHp: schema.fights.botAHp,
+    botBHp: schema.fights.botBHp,
+    botAId: schema.fights.botAId,
+    botBId: schema.fights.botBId,
+    createdAt: schema.fights.createdAt,
+    endedAt: schema.fights.endedAt,
+    id: schema.fights.id,
+    arena: schema.fights.arena,
+  }).from(schema.fights)
     .where(or(
       eq(schema.fights.botAId, bot.id),
       eq(schema.fights.botBId, bot.id),
     ))
     .orderBy(desc(schema.fights.createdAt))
-    .limit(10)
+
+  // Recent fights (last 10)
+  const fights = allFights.slice(0, 10)
 
   // Resolve opponent names
   const opponentIds = new Set<string>()
@@ -217,6 +230,15 @@ botsRouter.get('/:name/stats', async (c) => {
     }
   })
 
+  const achievements = computeAchievements(bot.id, {
+    wins: bot.wins,
+    losses: bot.losses,
+    winStreak: bot.winStreak,
+    bestStreak: bot.bestStreak,
+    tier: bot.tier,
+    eloRating: bot.eloRating,
+  }, allFights)
+
   return c.json({
     ...bot,
     tierName: TIER_NAMES[bot.tier] || 'BABY',
@@ -226,6 +248,7 @@ botsRouter.get('/:name/stats', async (c) => {
     rank,
     totalBots: allBots.length,
     recentFights,
+    achievements,
   })
 })