monitoring: add separate all-sensors temp panel with 70°C warning line

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

monitoring/grafana-temps-dashboard.yaml

@@ -73,6 +73,34 @@ data:
              "expr": "max by (instance) (node_hwmon_temp_celsius)",
              "legendFormat": "{{instance}}", "refId": "A"}
           ]
+        },
+        {
+          "datasource": {"type": "prometheus", "uid": "${datasource}"},
+          "fieldConfig": {
+            "defaults": {
+              "color": {"mode": "palette-classic"},
+              "unit": "celsius",
+              "custom": {"drawStyle": "line", "lineWidth": 1, "fillOpacity": 5, "showPoints": "never", "thresholdsStyle": {"mode": "line"}},
+              "thresholds": {"mode": "absolute", "steps": [
+                {"color": "green", "value": null},
+                {"color": "red", "value": 70}
+              ]}
+            },
+            "overrides": []
+          },
+          "gridPos": {"h": 8, "w": 24, "x": 0, "y": 8},
+          "id": 3,
+          "options": {
+            "legend": {"displayMode": "table", "placement": "bottom", "calcs": ["last", "max"]},
+            "tooltip": {"mode": "multi"}
+          },
+          "title": "All temperature sensors (warning line @ 70°C)",
+          "type": "timeseries",
+          "targets": [
+            {"datasource": {"type": "prometheus", "uid": "${datasource}"},
+             "expr": "node_hwmon_temp_celsius",
+             "legendFormat": "{{instance}} / {{chip}} / {{sensor}}", "refId": "A"}
+          ]
         }
       ],
       "refresh": "30s",
@@ -87,5 +115,5 @@ data:
       "timezone": "Europe/Oslo",
       "title": "Hardware Temperatures",
       "uid": "hw-temps",
-      "version": 2
+      "version": 3
     }