fix: add webhook delivery for monitoring alerts

DiskUsage and ContainerCrash alerts now fire webhooks via
send_webhook() after pushing WebSocket notifications. Added
data_dir parameter to spawn_metrics_collector for webhook config
access.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

core/archipelago/src/monitoring/mod.rs

@@ -1,5 +1,6 @@
 pub mod collector;
 
+use crate::webhooks::{self, WebhookEvent, WebhookPayload};
 use serde::{Deserialize, Serialize};
 use std::collections::VecDeque;
 use std::path::PathBuf;
@@ -481,6 +482,7 @@ async fn save_alert_rules(data_dir: &std::path::Path, rules: &[AlertRule]) -> an
 pub fn spawn_metrics_collector(
     store: Arc<MetricsStore>,
     state: Option<Arc<crate::state::StateManager>>,
+    data_dir: Option<PathBuf>,
 ) {
     tokio::spawn(async move {
         // Wait 30s for system to stabilize after boot
@@ -534,6 +536,31 @@ pub fn spawn_metrics_collector(
                             state_mgr.update_data(data).await;
                             info!("Fired {} alert(s)", alerts.len());
                         }
+
+                        // Fire-and-forget webhook delivery for mapped alert types
+                        if let Some(ref dir) = data_dir {
+                            for alert in &alerts {
+                                let event = match alert.kind {
+                                    AlertRuleKind::DiskUsage => Some(WebhookEvent::DiskWarning),
+                                    AlertRuleKind::ContainerCrash => Some(WebhookEvent::ContainerCrash),
+                                    _ => None,
+                                };
+                                if let Some(event) = event {
+                                    let payload = WebhookPayload {
+                                        event,
+                                        title: format!("{:?} Alert", alert.kind),
+                                        message: alert.message.clone(),
+                                        timestamp: chrono::Utc::now().to_rfc3339(),
+                                        node_id: String::new(),
+                                        details: Some(serde_json::json!({
+                                            "value": alert.value,
+                                            "threshold": alert.threshold,
+                                        })),
+                                    };
+                                    webhooks::send_webhook(dir, payload).await;
+                                }
+                            }
+                        }
                     }
                 }
                 Err(e) => {

core/archipelago/src/server.rs

@@ -77,7 +77,7 @@ impl Server {
 
         // Create metrics store and spawn background collector
         let metrics_store = Arc::new(MetricsStore::with_data_dir(config.data_dir.clone()));
-        crate::monitoring::spawn_metrics_collector(metrics_store.clone(), Some(state_manager.clone()));
+        crate::monitoring::spawn_metrics_collector(metrics_store.clone(), Some(state_manager.clone()), Some(config.data_dir.clone()));
 
         let api_handler = Arc::new(
             ApiHandler::new(config.clone(), state_manager.clone(), metrics_store).await?,