feat: Add Prometheus Unix exporter to Alloy for host metrics collection, update Docker Compose volumes, and enable Keepalived daemon mode.

vm1/alloy-config.alloy

@@ -55,3 +55,23 @@ loki.write "loki" {
     url = "http://192.168.1.200:3100/loki/api/v1/push"
   }
 }
+
+// Collect system metrics
+prometheus.exporter.unix "host" {
+  procfs_path = "/host/proc"
+  sysfs_path  = "/host/sys"
+  rootfs_path = "/host/root"
+}
+
+// Scrape metrics from the unix exporter
+prometheus.scrape "host" {
+  targets    = prometheus.exporter.unix.host.targets
+  forward_to = [prometheus.remote_write.mimir.receiver]
+}
+
+// Write metrics to Mimir/Prometheus
+prometheus.remote_write "mimir" {
+  endpoint {
+    url = "http://192.168.1.200:9090/api/v1/write"
+  }
+}