fix(installer): Add missing WIXUI_INSTALLDIR property and fix RemoveFolder ID

- Added WIXUI_INSTALLDIR property (required per WiX issue #7105)
- Changed RemoveFolder Id from "DesktopFolder" to "RemoveDesktopShortcut"
  to avoid ID conflict with StandardDirectory element

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <[email protected]>

Author: cfsmp3

windows/installer.wxs

@@ -14,6 +14,7 @@
 		<Icon Id="ccxgui.exe" SourceFile="./installer/ccxgui.exe"/>
 		<!-- Use standard WixUI_InstallDir dialog set -->
 		<ui:WixUI Id="WixUI_InstallDir" InstallDirectory="INSTALLFOLDER" />
+		<Property Id="WIXUI_INSTALLDIR" Value="INSTALLFOLDER"/>
 		<Property Id="ARPNOMODIFY" Value="1" />
 	</Package>
 	<Fragment>
@@ -24,7 +25,7 @@
                 Description="Run CCExtractor"
                 Target="[INSTALLFOLDER]ccxgui.exe"
                 WorkingDirectory="INSTALLFOLDER"/>
-            <RemoveFolder Id="DesktopFolder" On="uninstall"/>
+            <RemoveFolder Id="RemoveDesktopShortcut" On="uninstall"/>
             <RegistryValue
                 Root="HKCU"
                 Key="Software\CCExtractor\ccextractor"