fix(convex): mover cron jobs para API HTTP + crontab do Linux

Problema:
- Cron jobs do Convex criam registros em _scheduled_job_logs
- Convex self-hosted carrega TODAS as versoes em memoria
- 1488 execucoes/dia = ~45k registros/mes acumulando
- Uso de memoria chegando a 19GB, causando 12 OOM kills/dia

Solucao:
- Criar endpoints HTTP em /api/cron/* para substituir crons
- Desabilitar crons no Convex (comentados em crons.ts)
- Chamar endpoints via crontab do Linux

Novos arquivos:
- src/app/api/cron/chat-cleanup/route.ts
- src/app/api/cron/usb-cleanup/route.ts
- scripts-static/* (copiado da VPS para versionamento)

Documentacao:
- docs/OPERATIONS.md secao 12 com instrucoes do crontab

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

scripts-static/docker-compose.yml

@@ -0,0 +1,32 @@
+version: "3.8"
+
+services:
+  scripts_static:
+    image: nginx:1.27-alpine
+    networks:
+      - traefik_public
+    volumes:
+      - /root/scripts-static:/usr/share/nginx/html:ro
+    healthcheck:
+      test: ["CMD", "wget", "-qO-", "http://localhost"]
+      interval: 30s
+      timeout: 10s
+      retries: 3
+    deploy:
+      placement:
+        constraints:
+          - node.role == manager
+      labels:
+        - traefik.enable=true
+        - traefik.http.routers.scripts.rule=Host(`scripts.rever.com.br`)
+        - traefik.http.routers.scripts.entrypoints=websecure
+        - traefik.http.routers.scripts.tls.certresolver=le
+        - traefik.http.services.scripts.loadbalancer.server.port=80
+      restart_policy:
+        condition: any
+        delay: 5s
+        max_attempts: 3
+
+networks:
+  traefik_public:
+    external: true