Install SqlServer module via Save-Module to pwsh-only modules path (#608)

Install the `SqlServer` module via `Save-Module` into `C:\Program
Files\PowerShell\Modules` (pwsh-only path) instead of `pwsh -Command
'Install-Module …'`.

Why:
- Avoids the pwsh 7.6 PowerShellGet AV crash on Server 2022 by running
the install under Windows PowerShell 5.1.
- Targets the pwsh-only modules path, so PS 5.1 keeps resolving
`Invoke-Sqlcmd` to the existing SQLPS 16 — preserves the historical "two
worlds" split and avoids SqlServer 22's strict-SSL defaults breaking
in-container localhost SQL connections.
- pwsh 7 still gets `SqlServer 22.2.0` (verified via `Import-Module`
post-install).

Verified locally with `New-BcContainer` against freshly built ltsc2019,
ltsc2022, and ltsc2025 generic images — all reach "Ready for
connections!" and pass `Set SQL Server memory limit`.

---------

Co-authored-by: aholstrup1 <aholstrup1@users.noreply.github.com>

Author: aholstrup1

generic/Run/SetupGeneric2.ps1

@@ -3,7 +3,24 @@ Write-Host "only24=$env:only24"
 $filesonly = $env:filesonly -eq 'true'
 $only24 = $env:only24 -eq 'true'
 if (-not $filesonly) {
-    Write-Host 'Installing SqlServer Module in PowerShell 7'
-    pwsh -Command 'Install-Module -Name SqlServer -RequiredVersion 22.2.0 -Scope AllUsers -Force'
+    Write-Host 'Installing SqlServer Module to PowerShell 7 modules path'
+    [Net.ServicePointManager]::SecurityProtocol = [Net.ServicePointManager]::SecurityProtocol -bor [Net.SecurityProtocolType]::Tls12
+
+    Install-PackageProvider -Name NuGet -Force -Scope AllUsers | Out-Null
+    Set-PSRepository -Name PSGallery -InstallationPolicy Trusted
+
+    # Save to the pwsh-only modules path so PS 5.1 keeps resolving Invoke-Sqlcmd to SQLPS
+    $pwshModulesPath = 'C:\Program Files\PowerShell\Modules'
+    if (-not (Test-Path $pwshModulesPath)) {
+        New-Item -ItemType Directory -Path $pwshModulesPath -Force | Out-Null
+    }
+    Save-Module -Name SqlServer -RequiredVersion 22.2.0 -Path $pwshModulesPath -Force
+
+    Write-Host 'Verifying SqlServer module loads in PowerShell 7'
+    pwsh -NoProfile -Command 'Import-Module -Name SqlServer -RequiredVersion 22.2.0 -ErrorAction Stop'
+    if ($LASTEXITCODE -ne 0) {
+        throw "SqlServer module 22.2.0 failed to import in PowerShell 7 (pwsh exit $LASTEXITCODE)"
+    }
+
     Write-Host 'Done'
 }