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/migrations.ts

@@ -307,21 +307,21 @@ async function getTenantUsers(ctx: QueryCtx, tenantId: string) {
   return ctx.db
     .query("users")
     .withIndex("by_tenant", (q) => q.eq("tenantId", tenantId))
-    .collect()
+    .take(2000)
 }
 
 async function getTenantQueues(ctx: QueryCtx, tenantId: string) {
   return ctx.db
     .query("queues")
     .withIndex("by_tenant", (q) => q.eq("tenantId", tenantId))
-    .collect()
+    .take(500)
 }
 
 async function getTenantCompanies(ctx: QueryCtx, tenantId: string) {
   return ctx.db
     .query("companies")
     .withIndex("by_tenant", (q) => q.eq("tenantId", tenantId))
-    .collect()
+    .take(1000)
 }
 
 export const exportTenantSnapshot = query({
@@ -347,7 +347,7 @@ export const exportTenantSnapshot = query({
     const tickets = await ctx.db
       .query("tickets")
       .withIndex("by_tenant", (q) => q.eq("tenantId", tenantId))
-      .collect()
+      .take(5000)
 
     const ticketsWithRelations = []
 
@@ -355,12 +355,12 @@ export const exportTenantSnapshot = query({
       const comments = await ctx.db
         .query("ticketComments")
         .withIndex("by_ticket", (q) => q.eq("ticketId", ticket._id))
-        .collect()
+        .take(500)
 
       const events = await ctx.db
         .query("ticketEvents")
         .withIndex("by_ticket", (q) => q.eq("ticketId", ticket._id))
-        .collect()
+        .take(500)
 
       const requester = userMap.get(ticket.requesterId)
       const assignee = ticket.assigneeId ? userMap.get(ticket.assigneeId) : undefined
@@ -575,7 +575,7 @@ export const importPrismaSnapshot = mutation({
     const existingTenantUsers = await ctx.db
       .query("users")
       .withIndex("by_tenant", (q) => q.eq("tenantId", snapshot.tenantId))
-      .collect()
+      .take(2000)
 
     for (const user of existingTenantUsers) {
       const role = normalizeRole(user.role ?? null)
@@ -672,7 +672,7 @@ export const importPrismaSnapshot = mutation({
       const existingComments = await ctx.db
         .query("ticketComments")
         .withIndex("by_ticket", (q) => q.eq("ticketId", ticketId))
-        .collect()
+        .take(500)
       for (const comment of existingComments) {
         await ctx.db.delete(comment._id)
       }
@@ -680,7 +680,7 @@ export const importPrismaSnapshot = mutation({
       const existingEvents = await ctx.db
         .query("ticketEvents")
         .withIndex("by_ticket", (q) => q.eq("ticketId", ticketId))
-        .collect()
+        .take(500)
       for (const event of existingEvents) {
         await ctx.db.delete(event._id)
       }
@@ -765,7 +765,7 @@ export const backfillTicketCommentAuthorSnapshots = mutation({
         const events = await ctx.db
           .query("ticketEvents")
           .withIndex("by_ticket", (q) => q.eq("ticketId", comment.ticketId))
-          .collect()
+          .take(100)
         const matchingEvent = events.find(
           (event) => event.type === "COMMENT_ADDED" && event.createdAt === comment.createdAt,
         )