Add comprehensive test suite, fix minor issues, rename function and file names to match approved verbs (#708)

Scripts/CLI/Show-CliMenuOptions.ps1

@@ -0,0 +1,30 @@
+# Shows the CLI menu options and prompts the user to select one. Loops until a valid option is selected.
+function Show-CliMenuOptions {
+    Do { 
+        $ModeSelectionMessage = "Please select an option (1/2)" 
+
+        Write-CliHeader 'Menu'
+
+        Write-Host "(1) Default mode: Quickly apply the recommended changes"
+        Write-Host "(2) App removal mode: Select & remove apps, without making other changes"
+
+        # Only show this option if SavedSettings file exists
+        if (Test-Path $script:SavedSettingsFilePath) {
+            Write-Host "(3) Quickly apply your last used settings"
+            
+            $ModeSelectionMessage = "Please select an option (1/2/3)" 
+        }
+
+        Write-Host ""
+        Write-Host ""
+
+        $Mode = Read-Host $ModeSelectionMessage
+
+        if (($Mode -eq '3') -and -not (Test-Path $script:SavedSettingsFilePath)) {
+            $Mode = $null
+        }
+    }
+    while ($Mode -ne '1' -and $Mode -ne '2' -and $Mode -ne '3')
+
+    return $Mode
+}