setup-dev-env: fix Clang path for ARM64 hosts, fix .vsconfig doc link

- Use wildcard VC\Tools\Llvm\*\bin for Clang detection across host archs
- Link .vsconfig to GitHub repo URL instead of broken relative path

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: Ben Hillis

doc/docs/dev-loop.md

@@ -8,7 +8,7 @@ The following tools are required to build WSL:
 
 - CMake >= 3.25
     - Can be installed with `winget install Kitware.CMake`
-- Visual Studio with the following components (install via [`.vsconfig`](../../.vsconfig) — use VS Installer → More → Import configuration, or `winget install Microsoft.VisualStudio.2022.Community --override "--wait --quiet --config .vsconfig"`):
+- Visual Studio with the following components (install via [`.vsconfig`](https://github.com/microsoft/WSL/blob/master/.vsconfig) — use VS Installer → More → Import configuration, or `winget install Microsoft.VisualStudio.2022.Community --override "--wait --quiet --config .vsconfig"`):
     - Windows SDK 26100
     - MSBuild
     - Universal Windows platform support for v143 build tools (X64 and ARM64)

tools/setup-dev-env.ps1

@@ -89,7 +89,7 @@ if ($vsOk)
     Write-Host "Visual Studio Components:" -ForegroundColor White
 
     # Check for specific required components via their markers
-    $clangPath = Join-Path $vsInstall "VC\Tools\Llvm\x64\bin\clang-format.exe"
+    $clangPath = Join-Path $vsInstall "VC\Tools\Llvm\*\bin\clang-format.exe"
     Check "C++ Clang Compiler for Windows" (Test-Path $clangPath) $script:VsInstallFix
 
     $atlPath = Join-Path $vsInstall "VC\Tools\MSVC\*\atlmfc\include\atlbase.h"