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/deviceExportTemplates.ts

@@ -37,7 +37,7 @@ async function unsetDefaults(
   const templates = await ctx.db
     .query("deviceExportTemplates")
     .withIndex("by_tenant", (q) => q.eq("tenantId", tenantId))
-    .collect()
+    .take(100)
 
   await Promise.all(
     templates
@@ -73,7 +73,7 @@ export const list = query({
     const templates = await ctx.db
       .query("deviceExportTemplates")
       .withIndex("by_tenant", (q) => q.eq("tenantId", tenantId))
-      .collect()
+      .take(100)
 
     return templates
       .filter((tpl) => {
@@ -112,7 +112,7 @@ export const listForTenant = query({
     const templates = await ctx.db
       .query("deviceExportTemplates")
       .withIndex("by_tenant", (q) => q.eq("tenantId", tenantId))
-      .collect()
+      .take(100)
 
     return templates
       .filter((tpl) => tpl.isActive !== false)
@@ -149,7 +149,7 @@ export const getDefault = query({
           .withIndex("by_tenant_company", (q) => q.eq("tenantId", tenantId).eq("companyId", companyId))
       : ctx.db.query("deviceExportTemplates").withIndex("by_tenant_default", (q) => q.eq("tenantId", tenantId).eq("isDefault", true))
 
-    const templates = await indexQuery.collect()
+    const templates = await indexQuery.take(100)
     const candidate = templates.find((tpl) => tpl.isDefault) ?? null
     if (candidate) {
       return {
@@ -357,7 +357,7 @@ export const clearCompanyDefault = mutation({
     const templates = await ctx.db
       .query("deviceExportTemplates")
       .withIndex("by_tenant_company", (q) => q.eq("tenantId", tenantId).eq("companyId", companyId))
-      .collect()
+      .take(100)
     const now = Date.now()
     await Promise.all(
       templates.map((tpl) =>