Read the CPU temperature instead of the alarm threshold beside it

lm-sensors prints high= and crit= on the same line as the reading, so scraping
the line for its largest number reported a flat 100C on Intel while the shell's
last-field parse got a bare ")" and never fired at all. One parse in the
adapter now, preferring Tdie over Tctl since Tctl carries a +27C offset.

Plugin/unraid/include/common.php

@@ -507,6 +507,41 @@ function vv_ups_stats(): array {
     ];
 }
 
+// CPU temperature in °C, or null if no sensor answers.
+//
+// Mirror of platform_get_cpu_temp() in Plugin/unraid/adapter.sh — the two must agree, because the
+// Monitor card and the stability watchdog display and act on the same number, and for months they
+// did not. The PHP side scraped every decimal off the sensor line and took the largest, which on
+// any board printing "(high = +80.0 C, crit = +100.0 C)" is the critical threshold: HOST2 reported
+// a flat 100°C while sitting at 63. The shell side took the line's last field, which on that same
+// board is the literal ")", so its check silently never fired.
+//
+// Both defects came from parsing a line that carries three temperatures when only one of them is a
+// reading. The parenthetical is stripped before any digit is read.
+//
+// Tdie before Tctl for the AMD reason: Tctl carries a fixed offset (+27°C on Threadripper) and is
+// a control value, not a measurement — it is why HOST1 read 70 while the die was at 43.
+function vv_cpu_temp(): ?int {
+    $out = shell_exec('sensors 2>/dev/null') ?: '';
+    if (trim($out) === '') return null;
+
+    $out = preg_replace('/\(.*$/m', '', $out);      // drop "(high = ..., crit = ...)"
+
+    foreach (['Tdie', 'Package id 0', 'CPU Temp', 'Core '] as $label) {
+        $best = null;
+        foreach (explode("\n", $out) as $line) {
+            if (stripos(ltrim($line), $label) !== 0)                  continue;
+            if (!preg_match('/([+-]?\d+\.\d+)/', $line, $m))          continue;
+            $v = (float)$m[1];
+            // Max within a label: a multi-die part publishes one line per die, and the hottest is
+            // the one worth acting on.
+            if ($best === null || $v > $best) $best = $v;
+        }
+        if ($best !== null) return (int)round($best);
+    }
+    return null;
+}
+
 function vv_parity_status(): array {
     $var = [];
     foreach (@file('/var/local/emhttp/var.ini') ?: [] as $line) {