windows: embed LibreHardwareMonitorLib for better sensors detection

- Updated GitHub Actions release workflow to set up .NET and build the LHM executable.
- Modified Makefile to include a conditional build step for the .NET executable on Windows.

beszel/internal/agent/sensors_default.go

@@ -0,0 +1,9 @@
+//go:build !windows
+
+package agent
+
+import (
+	"github.com/shirou/gopsutil/v4/sensors"
+)
+
+var getSensorTemps = sensors.TemperaturesWithContext