feat(kafka): add Kafka integration for event streaming

- Introduced Kafka support in the Evolution API, allowing for real-time event streaming and processing.
- Updated environment configuration to include Kafka-related variables.
- Added KafkaController and KafkaRouter for managing Kafka events.
- Enhanced event management to support Kafka alongside existing integrations.
- Updated database schemas and migrations for Kafka integration in both MySQL and PostgreSQL.
- Documented Kafka integration in the README file.

prisma/postgresql-migrations/20250918182355_add_kafka_integration/migration.sql

@@ -0,0 +1,17 @@
+-- CreateTable
+CREATE TABLE "public"."Kafka" (
+    "id" TEXT NOT NULL,
+    "enabled" BOOLEAN NOT NULL DEFAULT false,
+    "events" JSONB NOT NULL,
+    "createdAt" TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    "updatedAt" TIMESTAMP NOT NULL,
+    "instanceId" TEXT NOT NULL,
+
+    CONSTRAINT "Kafka_pkey" PRIMARY KEY ("id")
+);
+
+-- CreateIndex
+CREATE UNIQUE INDEX "Kafka_instanceId_key" ON "public"."Kafka"("instanceId");
+
+-- AddForeignKey
+ALTER TABLE "public"."Kafka" ADD CONSTRAINT "Kafka_instanceId_fkey" FOREIGN KEY ("instanceId") REFERENCES "public"."Instance"("id") ON DELETE CASCADE ON UPDATE CASCADE;