hive-c0re: replace the agents_crashing banner with a crash-watcher log line + grafana alert

hive-sh4re/src/manager.rs

@@ -55,12 +55,6 @@ pub fn trusted_sender(s: &str) -> Ident {
 pub enum HelperEvent {
     /// A sub-agent's recorded flake rev is stale relative to hyperhive.
     NeedsUpdate { agent: String },
-    /// Container exited without an operator-initiated stop (crash).
-    ContainerCrash {
-        agent: String,
-        #[serde(default, skip_serializing_if = "Option::is_none")]
-        note: Option<String>,
-    },
 }
 
 #[cfg(test)]