Constant HEALTH_CHECK 

pub const HEALTH_CHECK: &str = "machine HealthCheck<T> {\r\n    state Healthy(status: T)\r\n    state Degraded(status: T, failures: i64)\r\n    state Unhealthy(reason: String)\r\n\r\n    transition probe: Healthy -> Healthy | Degraded | Unhealthy\r\n    transition recover: Degraded -> Healthy | Unhealthy\r\n\r\n    async effect run_probe() -> Result<T, String>\r\n\r\n    async on probe() {\r\n        let result = perform run_probe();\r\n        match result {\r\n            Ok(next_status) => {\r\n                goto Healthy(next_status);\r\n            }\r\n            Err(err) => {\r\n                goto Degraded(status, 1);\r\n            }\r\n        }\r\n    }\r\n\r\n    async on recover() {\r\n        let result = perform run_probe();\r\n        match result {\r\n            Ok(next_status) => {\r\n                goto Healthy(next_status);\r\n            }\r\n            Err(err) => {\r\n                goto Unhealthy(err);\r\n            }\r\n        }\r\n    }\r\n}\r\n";

The Gust source for the HealthCheck machine.

Models service health monitoring with three states:

• Healthy – the service is operating normally.
• Degraded – some health checks are failing but the service is partially functional; tracks a failure count.
• Unhealthy – the service is down, with a reason string.

Generic over T for the health status payload type.