feat(update): persist interactive install choices

scripts/lib/install-options.ps1

@@ -0,0 +1,72 @@
+function Read-InstallBoolean {
+    param([string]$Prompt, [bool]$Default)
+    $hint = if ($Default) { 'Y/n' } else { 'y/N' }
+    while ($true) {
+        Write-Host "$Prompt [$hint] " -NoNewline
+        $answer = [Console]::ReadLine()
+        if ($null -eq $answer) { throw 'Input ended before install options were confirmed.' }
+        switch ($answer.Trim().ToLowerInvariant()) {
+            '' { return $Default }
+            { $_ -in @('y', 'yes') } { return $true }
+            { $_ -in @('n', 'no') } { return $false }
+        }
+    }
+}
+
+function Read-InstallOptions {
+    param([string]$HomePath, [string]$RepositoryRoot, [string]$Client, [switch]$DryRun)
+    $defaults = @{ update_agents = $false; flashbang = $true }
+    if (Test-Path -LiteralPath (Join-Path $HomePath '.my-ai-configuration/selection.json')) {
+        try { $defaults = Read-UpdateSelection -HomePath $HomePath -RepositoryRoot $RepositoryRoot -AllowLegacy }
+        catch { Write-Warning 'Saved options could not be read; confirm new options below.' }
+    }
+    if ($DryRun) { return $defaults }
+    return @{
+        update_agents = Read-InstallBoolean -Prompt "Update selected agent CLIs ($Client)?" -Default $defaults.update_agents
+        flashbang = Read-InstallBoolean -Prompt 'Enable the Flashbang notification hook?' -Default $defaults.flashbang
+    }
+}
+
+function Test-CodexProcessActive {
+    if ([Environment]::OSVersion.Platform -ne [PlatformID]::Win32NT) { return $false }
+    return [bool](Get-Process -Name 'codex' -ErrorAction SilentlyContinue)
+}
+
+function Test-GlobalNpmCodex {
+    $npm = Get-Command npm -ErrorAction SilentlyContinue
+    if (-not $npm) { return $false }
+    $previousPreference = $ErrorActionPreference
+    try {
+        $ErrorActionPreference = 'Continue'
+        & $npm list -g '@openai/codex' --depth=0 --json 1>$null 2>$null
+        return $LASTEXITCODE -eq 0
+    } finally {
+        $ErrorActionPreference = $previousPreference
+    }
+}
+
+function Update-SelectedAgentClis {
+    param([string]$Client, [switch]$DryRun, [switch]$Summary)
+    $clients = if ($Client -eq 'Both') { @('codex', 'claude') } else { @($Client.ToLowerInvariant()) }
+    $previousNonInteractive = $script:PluginNonInteractive
+    $previousAutoUpdate = $env:CLAUDE_CODE_PACKAGE_MANAGER_AUTO_UPDATE
+    try {
+        $script:PluginNonInteractive = $true
+        $env:CLAUDE_CODE_PACKAGE_MANAGER_AUTO_UPDATE = '1'
+        foreach ($selectedClient in $clients) {
+            if ($selectedClient -eq 'codex' -and -not $DryRun -and (Test-CodexProcessActive)) {
+                Write-Warning 'Codex CLI update skipped because codex.exe is running. Close all Codex sessions and run the update again to update the CLI.'
+                continue
+            }
+            if ($selectedClient -eq 'codex' -and (Test-GlobalNpmCodex)) {
+                Invoke-PluginCommand -Command 'npm' -Arguments @('install','-g','@openai/codex@latest') -DryRun:$DryRun -Summary:$Summary
+            } else {
+                Invoke-PluginCommand -Command $selectedClient -Arguments @('update') -DryRun:$DryRun -Summary:$Summary
+            }
+            if ($Summary) { Write-Output "CLI $selectedClient update: $(if ($DryRun) { 'dry-run' } else { 'PASS' })" }
+        }
+    } finally {
+        $script:PluginNonInteractive = $previousNonInteractive
+        $env:CLAUDE_CODE_PACKAGE_MANAGER_AUTO_UPDATE = $previousAutoUpdate
+    }
+}