Improve service checks and system health details

store.go

@@ -126,6 +126,7 @@ func openStore(path string) (*Store, error) {
 	}
 	// Older databases get this column without requiring a separate migration tool.
 	_, _ = db.Exec(`ALTER TABLE alert_events ADD COLUMN recovery_sent_at INTEGER`)
+	_, _ = db.Exec(`ALTER TABLE service_checks ADD COLUMN endpoint TEXT NOT NULL DEFAULT 'public'`)
 	_, _ = db.Exec(`PRAGMA foreign_keys=ON`)
 	return &Store{db: db}, nil
 }