Add basic lgtm-stack (WIP)

playbooks/roles/lgtm_stack/templates/config.alloy.j2

@@ -0,0 +1,24 @@
+logging {
+  level  = "info"
+  format = "logfmt"
+}
+
+prometheus.exporter.self "alloy" {}
+prometheus.scrape "alloy" {
+	targets    = prometheus.exporter.self.alloy.targets
+	forward_to = [prometheus.remote_write.mimir.receiver]
+}
+
+// prometheus.exporter.node_exporter "node_exporter" {}
+prometheus.scrape "node_exporter" {
+  targets = [
+    {"__address__" = "node_exporter:9100", "job" = "node_exporter"},
+  ]
+  forward_to = [prometheus.remote_write.mimir.receiver]
+}
+
+prometheus.remote_write "mimir" {
+	endpoint {
+		url = "https://{{ lgtm_stack_mimir_domain }}/api/v1/push"
+	}
+}