[CONFIGURE] Add support for MSVC 2026 (reactos#8457)

Visual Studio 2026 is now generally available, read https://devblogs.microsoft.com/visualstudio/visual-studio-2026-is-here-faster-smarter-and-a-hit-with-early-adopters/ for more information.

It seems MSVC 2026 still support setting the subsystem 5.1/5.2, although they remove the Windows 8.1 and earlier support for VCRuntime and STL in MSVC 2026.

Author: MouriNaruto

configure.cmd

@@ -56,6 +56,7 @@ if defined ROS_ARCH (
     cl 2>&1 | findstr /R /c:"19\.2.\." > NUL && set VS_VERSION=16
     cl 2>&1 | findstr /R /c:"19\.3.\." > NUL && set VS_VERSION=17
     cl 2>&1 | findstr /R /c:"19\.4.\." > NUL && set VS_VERSION=17
+    cl 2>&1 | findstr /R /c:"19\.5.\." > NUL && set VS_VERSION=18
     if not defined VS_VERSION (
         echo Error: Visual Studio version too old ^(before 14 ^(2015^)^) or version detection failed.
         goto quit