FEAT: re-enable and configure alertmanager

* disable components for k3s
* mute Watchdog alert
* configure pushover

reverts 96ffe5f

vars/helm.yml

@@ -6,8 +6,34 @@ helm_charts:
     chart: prometheus-community/kube-prometheus-stack
     namespace: metrics
     vals:
-      alertmanager:
+      kubeProxy:
         enabled: false
+      kubeScheduler:
+        enabled: false
+      kubeControllerManager:
+        enabled: false
+      alertmanager:
+        config:
+          global:
+            resolve_timeout: 5m
+          route:
+            group_by: ['alertname', 'cluster']
+            group_wait: 30s
+            group_interval: 5m
+            repeat_interval: 12h
+            receiver: 'pushover'
+            routes:
+              - receiver: 'null'
+                matchers:
+                  - alertname="Watchdog"
+          receivers:
+            - name: 'null'
+            - name: 'pushover'
+              pushover_configs:
+                - user_key: x9PipXt1zGOU31OJH9Osv18BFrlRhw
+                  token: aqvce1uukerhxhayxdq85wgtdh2c5r
+          templates:
+            - '/etc/alertmanager/config/*.tmpl'
       prometheus:
         prometheusSpec:
           storageSpec: