List instances

{
    "success": true,
    "instances": [
        {
            "instance_id": "BRK-123456D",
            "name": "ml-training-server",
            "region": "FINLAND-1",
            "ssh_key_name": "my-ssh-key",
            "fixed_ip": "10.0.1.5",
            "floating_ip": "203.0.113.45",
            "status": "RUNNING",
            "specs": {
                "gpu_type": "H100-SXM5-80GB",
                "gpu_count": 4,
                "cpu": 32,
                "ram": 256
            },
            "image": {
                "name": "Ubuntu 22.04"
            },
            "created_at": "2025-01-15T10:30:00Z",
            "currency": "USD",
            "operations": {
                "security_rules": false,
                "snapshot": false,
                "is_snapshotting": false,
                "hibernation": true,
                "restore_hibernation": false,
                "reboot": false
            }
        }
    ],
    "currency_context": "USD",
    "total_count": 45,
    "page": 1,
    "limit": 50,
    "has_next": false
}