feat: implement Call Center queues (mod_callcenter)

- Investigated the real callcenter_config command surface via
  'help callcenter_config' on the running FreeSWITCH before writing any
  code: queues only have load/unload/reload (static XML + reload, no
  'queue add' exists), while agents and tiers are fully dynamic via ESL
  commands (agent add, tier add) -- no file involved. This shapes the next
  phase (Agents/Tiers) differently from this one.
- queues table (tenant-scoped, RLS): strategy, moh/announce, wait times,
  tier rules, discard/abandoned handling, skip-agents-with-external-calls,
  recording_enabled
- packages/telephony: buildQueueXml()
- infrastructure/freeswitch: our own callcenter.conf.xml override (empties
  the vanilla static agents/tiers -- those become fully dynamic in the next
  phase) that includes callcenter_queues.conf.d/*.xml via X-PRE-PROCESS,
  same pattern as the Sofia gateway directory
- apps/api/src/queues: CRUD (POST/GET/GET:id/DELETE) using the queues.view/
  .manage permissions already in the seed
- b2bcall-fs-config (queue-sync.ts): one XML file per queue on a shared
  volume, synced via Redis pub/sub (b2bcall:queues:sync) on create/delete
  and once at boot -- same shape as trunk-sync.ts
- confirmed manually against the real FreeSWITCH, before coding the sync
  logic: 'queue load <name>' fails ('Invalid Queue not found!') for a file
  added after boot -- needs 'reloadxml' first to repopulate the in-memory
  XML tree from disk; after that, 'queue reload <name>' alone handles both
  create and update, no need to distinguish load vs reload
- verified end-to-end: created a queue (ROUND_ROBIN, maxWaitTime=120,
  discardAbandonedAfter=90), 'callcenter_config queue list' showed the
  correct values on the FreeSWITCH side; deleted it, list went back empty

docs/QUEUES.md

packages/database/prisma/migrations/20260828120508_queues/migration.sql

@@ -0,0 +1,44 @@
+-- CreateEnum
+CREATE TYPE "queue_strategy" AS ENUM ('LONGEST_IDLE_AGENT', 'ROUND_ROBIN', 'TOP_DOWN', 'AGENT_WITH_LEAST_TALK_TIME', 'AGENT_WITH_FEWEST_CALLS', 'SEQUENTIALLY_BY_AGENT_ORDER', 'RING_ALL', 'RING_PROGRESSIVELY');
+
+-- CreateTable
+CREATE TABLE "queues" (
+    "id" UUID NOT NULL,
+    "tenant_id" UUID NOT NULL,
+    "name" TEXT NOT NULL,
+    "description" TEXT,
+    "strategy" "queue_strategy" NOT NULL DEFAULT 'LONGEST_IDLE_AGENT',
+    "moh_sound" TEXT,
+    "announce_sound" TEXT,
+    "announce_frequency" INTEGER NOT NULL DEFAULT 0,
+    "max_wait_time" INTEGER NOT NULL DEFAULT 0,
+    "max_wait_time_with_no_agent" INTEGER NOT NULL DEFAULT 0,
+    "agent_no_answer_status" TEXT,
+    "tier_rules_apply" BOOLEAN NOT NULL DEFAULT false,
+    "tier_rule_wait_second" INTEGER NOT NULL DEFAULT 300,
+    "discard_abandoned_after" INTEGER NOT NULL DEFAULT 60,
+    "abandoned_resume_allowed" BOOLEAN NOT NULL DEFAULT false,
+    "skip_agents_with_external_calls" BOOLEAN NOT NULL DEFAULT true,
+    "recording_enabled" BOOLEAN NOT NULL DEFAULT false,
+    "enabled" BOOLEAN NOT NULL DEFAULT true,
+    "created_at" TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    "updated_at" TIMESTAMP(3) NOT NULL,
+    "deleted_at" TIMESTAMP(3),
+
+    CONSTRAINT "queues_pkey" PRIMARY KEY ("id")
+);
+
+-- CreateIndex
+CREATE INDEX "queues_tenant_id_idx" ON "queues"("tenant_id");
+
+-- CreateIndex
+CREATE UNIQUE INDEX "queues_tenant_id_name_key" ON "queues"("tenant_id", "name");
+
+-- AddForeignKey
+ALTER TABLE "queues" ADD CONSTRAINT "queues_tenant_id_fkey" FOREIGN KEY ("tenant_id") REFERENCES "tenants"("id") ON DELETE RESTRICT ON UPDATE CASCADE;
+
+-- Tabela de negocio tenant-scoped: RLS obrigatorio (ver docs/TENANT_ISOLATION.md).
+ALTER TABLE "queues" ENABLE ROW LEVEL SECURITY;
+ALTER TABLE "queues" FORCE ROW LEVEL SECURITY;
+CREATE POLICY "tenant_isolation" ON "queues"
+  USING (tenant_id = NULLIF(current_setting('app.current_tenant_id', true), '')::uuid);