fix(monitoring): ignore floating nct6775 temperature inputs

CPUTIN and AUXTIN* read 101 C or saturate at -128/127 C with no sensor wired,
so the alert fired while the CPU package stayed near 53 C.

Assisted-by: DeepSeek Harness (deepseek-flash)

hosts/12kingdoms-youko/homelab-services/monitoring/alert_rules/node-exporter.yml

@@ -309,8 +309,8 @@ groups:
       - alert: HostPhysicalComponentTooHot
         expr:
           '((node_hwmon_temp_celsius * ignoring(label) group_left(instance, job, node, sensor)
-          node_hwmon_sensor_label{label!~"(?i)^(tctl|tccd|tdie)$"} > 75)) * on(instance) group_left
-          (nodename) node_uname_info{nodename=~".+"}'
+          node_hwmon_sensor_label{label!~"(?i)^(tctl|tccd|tdie|auxtin[0-9]*|cputin)$"} > 75)) *
+          on(instance) group_left (nodename) node_uname_info{nodename=~".+"}'
         for: 5m
         labels:
           severity: warning