feat: add config-driven AppX package removal tab

- Add config/appx.json with curated list of removable AppX packages

- Add AppX Removal tab (WPFTab6) with Select All, Clear, and Remove buttons

- Reuse existing Invoke-WPFUIElements engine for minimal code footprint

- Add Invoke-WPFAppxRemoval.ps1 for background runspace package removal

- Add theme colors for the new tab button in light and dark modes

functions/public/Invoke-WPFSelectedCheckboxesUpdate.ps1

@@ -30,6 +30,7 @@ function Invoke-WPFSelectedCheckboxesUpdate{
                 elseif ($appKey.StartsWith("WPFTweaks")) { "Tweaks" }
                 elseif ($appKey.StartsWith("WPFToggle")) { "Toggle" }
                 elseif ($appKey.StartsWith("WPFFeature")) { "Feature" }
+                elseif ($appKey.StartsWith("WPFAppx")) { "Appx" }
                 else { "na" }
 
     switch ($group) {
@@ -81,6 +82,16 @@ function Invoke-WPFSelectedCheckboxesUpdate{
                 $sync.selectedFeatures.Remove($appKey)
             }
         }
+        "Appx" {
+            if ($type -eq "Add") {
+                if (!$sync.selectedAppx.Contains($appKey)) {
+                    $sync.selectedAppx.Add($appKey)
+                }
+            }
+            else{
+                $sync.selectedAppx.Remove($appKey)
+            }
+        }
         default {
             Write-Host "Unknown group for checkbox: $($appKey)"
         }