fix(convex): corrigir memory leak com .collect() sem limite e adicionar otimizacoes

Problema: Convex backend consumindo 16GB+ de RAM causando OOM kills

Correcoes aplicadas:
- Substituido todos os .collect() por .take(LIMIT) em 27+ arquivos
- Adicionado indice by_usbPolicyStatus para otimizar query de maquinas
- Corrigido N+1 problem em alerts.ts usando Map lookup
- Corrigido full table scan em usbPolicy.ts
- Corrigido subscription leaks no frontend (tickets-view, use-ticket-categories)
- Atualizado versao do Convex backend para precompiled-2025-12-04-cc6af4c

Arquivos principais modificados:
- convex/*.ts - limites em todas as queries .collect()
- convex/schema.ts - novo indice by_usbPolicyStatus
- convex/alerts.ts - N+1 fix com Map
- convex/usbPolicy.ts - uso do novo indice
- src/components/tickets/tickets-view.tsx - skip condicional
- src/hooks/use-ticket-categories.ts - skip condicional

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

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/components/admin/devices/admin-devices-overview.tsx

@@ -906,6 +906,8 @@ export type DevicesQueryItem = {
   linkedUsers?: Array<{ id: string; email: string; name: string }>
   remoteAccessEntries: DeviceRemoteAccessEntry[]
   customFields?: Array<{ fieldId?: string; fieldKey: string; label: string; type?: string; value: unknown; displayValue?: string }>
+  usbPolicy?: "ALLOW_ALL" | "BLOCK_ALL" | "WHITELIST" | null
+  usbPolicyStatus?: "IDLE" | "PENDING" | "APPLYING" | "APPLIED" | "FAILED" | null
 }
 
 export function normalizeDeviceItem(raw: Record<string, unknown>): DevicesQueryItem {

src/components/tickets/tickets-view.tsx

@@ -78,7 +78,10 @@ export function TicketsView({ initialFilters }: TicketsViewProps = {}) {
     queuesEnabled ? { tenantId, viewerId: convexUserId as Id<"users"> } : "skip"
   )
   const queues: TicketQueueSummary[] = Array.isArray(queuesResult) ? queuesResult : []
-  const agents = useQuery(api.users.listAgents, { tenantId }) as { _id: string; name: string }[] | undefined
+  const agents = useQuery(
+    api.users.listAgents,
+    isStaff && convexUserId ? { tenantId } : "skip"
+  ) as { _id: string; name: string }[] | undefined
 
   // Argumentos para a query paginada de tickets
   const ticketsArgs = useMemo(() => {