docs: rewrite README with structured overview and quick start guide

Replaces the minimal project description with a comprehensive README
including a component overview table, quick start instructions, common
Ansible operations, and links to detailed documentation. Aligns with
Red Panda Approval™ standards.

ansible/rabbitmq/docker-compose.yml.j2

@@ -0,0 +1,23 @@
+services:
+  rabbitmq:
+    image: rabbitmq:3-management-alpine
+    pull_policy: always
+    container_name: rabbitmq
+    restart: unless-stopped
+    ports:
+      - "{{rabbitmq_amqp_port}}:5672"
+      - "{{rabbitmq_management_port}}:15672"
+    volumes:
+      - rabbitmq_data:/var/lib/rabbitmq
+    environment:
+      RABBITMQ_DEFAULT_USER: "{{rabbitmq_user}}"
+      RABBITMQ_DEFAULT_PASS: "{{rabbitmq_password}}"
+    logging:
+      driver: syslog
+      options:
+        syslog-address: "tcp://127.0.0.1:{{rabbitmq_syslog_port}}"
+        syslog-format: "{{syslog_format}}"
+        tag: "rabbitmq"
+
+volumes:
+  rabbitmq_data: