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>

convex/queues.ts

@@ -81,12 +81,12 @@ export const list = query({
     const queues = await ctx.db
       .query("queues")
       .withIndex("by_tenant", (q) => q.eq("tenantId", tenantId))
-      .collect();
+      .take(50);
 
     const teams = await ctx.db
       .query("teams")
       .withIndex("by_tenant_name", (q) => q.eq("tenantId", tenantId))
-      .collect();
+      .take(50);
 
     return queues.map((queue) => {
       const team = queue.teamId ? teams.find((item) => item._id === queue.teamId) : null;
@@ -109,13 +109,13 @@ export const summary = query({
   args: { tenantId: v.string(), viewerId: v.id("users") },
   handler: async (ctx, { tenantId, viewerId }) => {
     await requireStaff(ctx, viewerId, tenantId);
-    const queues = await ctx.db.query("queues").withIndex("by_tenant", (q) => q.eq("tenantId", tenantId)).collect();
+    const queues = await ctx.db.query("queues").withIndex("by_tenant", (q) => q.eq("tenantId", tenantId)).take(50);
     const result = await Promise.all(
       queues.map(async (qItem) => {
         const tickets = await ctx.db
           .query("tickets")
           .withIndex("by_tenant_queue", (q) => q.eq("tenantId", tenantId).eq("queueId", qItem._id))
-          .collect();
+          .take(50);
         let pending = 0;
         let inProgress = 0;
         let paused = 0;