[windows] fix invalid arm64 toolchain path

Author: charles-zablit

utils/build.ps1

@@ -279,7 +279,7 @@ $DefaultPinned = @{
   };
   ARM64 = @{
     PinnedBuild = "https://download.swift.org/development/windows10-arm64/swift-DEVELOPMENT-SNAPSHOT-2025-11-03-a/swift-DEVELOPMENT-SNAPSHOT-2025-11-03-a-windows10-arm64.exe"
-    PinnedSHA256 = "A4394A53082BC0346A0D85C6B4A52F540A29517D594288707B8C1D6BAA0B9E55";
+    PinnedSHA256 = "D3F22B491E91F65996861246262D069BFA150E55DECBCB4AEE9FC6C7FD529F18";
     PinnedVersion = "0.0.0";
   };
 }
@@ -1444,7 +1444,7 @@ function Get-Dependencies {
 }
 
 function Get-PinnedToolchainToolsDir() {
-  $ToolchainName = $PinnedToolchain.TrimStart("swift-").TrimEnd("-a-windows10")
+  $ToolchainName = $PinnedToolchain.TrimStart("swift-").TrimEnd("-arm64").TrimEnd("-a-windows10")
 
   $ToolchainsRoot = [IO.Path]::Combine("$BinaryCache\toolchains", "$ToolchainName", "LocalApp", "Programs", "Swift", "Toolchains")
 
@@ -1471,15 +1471,15 @@ function Get-PinnedToolchainToolsDir() {
 }
 
 function Get-PinnedToolchainSDK([OS] $OS = $BuildPlatform.OS, [string] $Identifier = $OS.ToString()) {
-  $ToolchainName = $PinnedToolchain.TrimStart("swift-").TrimEnd("-a-windows10")
+  $ToolchainName = $PinnedToolchain.TrimStart("swift-").TrimEnd("-arm64").TrimEnd("-a-windows10")
 
   return [IO.Path]::Combine("$BinaryCache\", "toolchains", $ToolchainName,
     "LocalApp", "Programs", "Swift", "Platforms", (Get-PinnedToolchainVersion),
     "$($OS.ToString()).platform", "Developer", "SDKs", "$Identifier.sdk")
 }
 
 function Get-PinnedToolchainRuntime() {
-  $ToolchainName = $PinnedToolchain.TrimStart("swift-").TrimEnd("-a-windows10")
+  $ToolchainName = $PinnedToolchain.TrimStart("swift-").TrimEnd("-arm64").TrimEnd("-a-windows10")
 
   return [IO.Path]::Combine("$BinaryCache\", "toolchains", $ToolchainName,
     "LocalApp", "Programs", "Swift", "Runtimes", (Get-PinnedToolchainVersion),