perf: skip missed ticks on all intervals, reduce scan frequency

Prevents burst of health checks, scans, and snapshots after slow
podman responses by using MissedTickBehavior::Skip. Bumps container
scan interval from 30s to 60s to reduce DB lock contention.

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

core/archipelago/src/monitoring/mod.rs

@@ -29,6 +29,7 @@ pub fn spawn_metrics_collector(
         tokio::time::sleep(std::time::Duration::from_secs(60)).await;
 
         let mut interval = tokio::time::interval(std::time::Duration::from_secs(300));
+        interval.set_missed_tick_behavior(tokio::time::MissedTickBehavior::Skip);
 
         loop {
             interval.tick().await;