Release 0.4.5: installer DB wizard, credential key, lean offline Setup.

Choose bundled or external PostgreSQL in the Setup wizard with connection
validation; optional NETX_CREDENTIAL_SECRET_KEY; single desktop shortcut;
faster uninstall and tray startup for offline Windows packages.

Co-authored-by: Cursor <cursoragent@cursor.com>

packaging/stop_netx_app.ps1

@@ -1,7 +1,8 @@
-param(
+param(
     [string]$ProgramRoot = "",
     [string]$DataRoot = "",
-    [switch]$KeepPostgres = $false
+    [switch]$KeepPostgres = $false,
+    [switch]$KillTray = $false
 )
 
 $ErrorActionPreference = "Continue"
@@ -21,11 +22,17 @@ if (-not (Test-Path $stopScript)) {
 }
 if (Test-Path $stopScript) {
     Write-Host "==> Stopping NetX processes"
-    & powershell -ExecutionPolicy Bypass -File $stopScript -Force
+    Start-NetxPowerShell -File $stopScript -Arguments @("-Force") `
+        -WorkingDirectory $prog -WindowStyle Hidden -Wait | Out-Null
 } else {
     Write-Host "[WARN] stop_netx.ps1 not found"
 }
 
+if ($KillTray) {
+    Write-Host "==> Stopping NetX tray icons"
+    Stop-NetxTrayProcesses -ProgramRoot $prog
+}
+
 $mode = Get-DbMode -EnvMap $map
 if ($mode -eq "bundled" -and -not $KeepPostgres) {
     $pgBinCandidates = @(