Install Qt 6.10.3 by default

ws2tcp-local-gui needs qt_generate_deploy_app_script INCLUDE_PLUGINS, which
Qt 6.8 does not support.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

seediso/windows11/60-Install-Qt6.bat

@@ -5,7 +5,7 @@ title Install Qt 6
 rem Qt is not available from winget, so this uses the standalone aqtinstall (aqt) to fetch it.
 rem The msvc2022_64 build needs the MSVC Build Tools (see 20-Install-MSVC2022-BuildTools.bat).
 
-set "QT_VERSION=6.8.3"
+set "QT_VERSION=6.10.3"
 set "QT_ARCH=win64_msvc2022_64"
 set "QT_ROOT=C:\Qt"
 set "AQT=%TEMP%\aqt.exe"