feat: production hardening — background fights, queue tuning, CORS, cycling taglines

- Background fight loop: mock bots auto-fight every ~45s for site activity
  - Quiet hours (2-8 UTC) run 4x slower, jitter prevents robotic timing
  - Configurable via FIGHT_LOOP_ENABLED, FIGHT_LOOP_INTERVAL_MS
- Queue timeout: 30s in prod (was 3s), configurable via QUEUE_TIMEOUT_MS
- CORS: env-configurable via CORS_ORIGIN (default '*')
- Homepage: 40 cycling taglines with typewriter effect
- docker-compose: document all new env vars

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

docker-compose.yml

@@ -10,6 +10,15 @@ services:
     environment:
       - NODE_ENV=production
       - PORT=9100
+      # Queue: how long (ms) before falling back to mock bot (default 30s in prod)
+      # - QUEUE_TIMEOUT_MS=30000
+      # CORS: set to your domain in prod, or leave for same-origin
+      # - CORS_ORIGIN=https://botfights.example.com
+      # Background fights: mock bots fight each other for site activity
+      - FIGHT_LOOP_ENABLED=true
+      # - FIGHT_LOOP_INTERVAL_MS=45000
+      # - FIGHT_LOOP_QUIET_START=2
+      # - FIGHT_LOOP_QUIET_END=8
 
 volumes:
   botfights-data: