feat: add system tray and __main__ entry point

Add pystray-based system tray icon with Open UI / Restart / Quit
actions. Add __main__.py for `python -m wled_controller` support.
Update start-hidden.vbs with embedded Python fallback for both
installed and dev environments.

server/restart.ps1

@@ -1,7 +1,7 @@
 # Restart the WLED Screen Controller server
 # Stop any running instance
 $procs = Get-CimInstance Win32_Process -Filter "Name='python.exe'" |
-    Where-Object { $_.CommandLine -like '*wled_controller.main*' }
+    Where-Object { $_.CommandLine -like '*wled_controller*' -and $_.CommandLine -notlike '*demo*' -and $_.CommandLine -notlike '*vscode*' -and $_.CommandLine -notlike '*isort*' }
 foreach ($p in $procs) {
     Write-Host "Stopping server (PID $($p.ProcessId))..."
     Stop-Process -Id $p.ProcessId -Force -ErrorAction SilentlyContinue
@@ -21,7 +21,12 @@ if ($regUser) {
 
 # Start server detached
 Write-Host "Starting server..."
-Start-Process -FilePath python -ArgumentList '-m', 'wled_controller.main' `
+$pythonExe = (Get-Command python -ErrorAction SilentlyContinue).Source
+if (-not $pythonExe) {
+    # Fallback to known install location
+    $pythonExe = "$env:LOCALAPPDATA\Programs\Python\Python313\python.exe"
+}
+Start-Process -FilePath $pythonExe -ArgumentList '-m', 'wled_controller' `
     -WorkingDirectory 'c:\Users\Alexei\Documents\wled-screen-controller\server' `
     -WindowStyle Hidden
 
@@ -29,7 +34,7 @@ Start-Sleep -Seconds 3
 
 # Verify it's running
 $check = Get-CimInstance Win32_Process -Filter "Name='python.exe'" |
-    Where-Object { $_.CommandLine -like '*wled_controller.main*' }
+    Where-Object { $_.CommandLine -like '*wled_controller*' -and $_.CommandLine -notlike '*demo*' -and $_.CommandLine -notlike '*vscode*' -and $_.CommandLine -notlike '*isort*' }
 if ($check) {
     Write-Host "Server started (PID $($check[0].ProcessId))"
 } else {