Add Win32 service to run Sunshine as LocalSystem on login

tools/install-service.bat

@@ -0,0 +1,24 @@
+@echo off
+
+set SERVICE_NAME=sunshinesvc
+set SERVICE_BIN="%~dp0\tools\sunshinesvc.exe"
+set SERVICE_START_TYPE=auto
+
+rem Check if sunshinesvc already exists
+sc qc %SERVICE_NAME% > nul 2>&1
+if %ERRORLEVEL%==0 (
+    rem Stop the existing service if running
+    net stop %SERVICE_NAME%
+
+    rem Reconfigure the existing service
+    set SC_CMD=config
+) else (
+    rem Create a new service
+    set SC_CMD=create
+)
+
+rem Run the sc command to create/reconfigure the service
+sc %SC_CMD% %SERVICE_NAME% binPath= %SERVICE_BIN% start= %SERVICE_START_TYPE%
+
+rem Start the new service
+net start %SERVICE_NAME%