fix(ci): write Windows sha256 as LF

PowerShell Out-File emitted CRLF, so 'sha256sum -c' / 'shasum -c'
choked on the trailing CR in the filename (cross-platform verify of
the Windows artifact failed). Use [IO.File]::WriteAllText with a LF
and no BOM, matching the unix shasum sidecar format. Binaries were
always intact; only the sidecar was malformed.

Author: Teerapat-Vatpitak

.github/workflows/release.yml

@@ -67,8 +67,10 @@ jobs:
           Copy-Item "target/${{ matrix.target }}/release/mcp-loadtest.exe" $dir
           Copy-Item README.md, LICENSE-MIT, LICENSE-APACHE $dir
           Compress-Archive -Path $dir -DestinationPath "$dir.zip"
-          "$((Get-FileHash "$dir.zip" -Algorithm SHA256).Hash.ToLower())  $dir.zip" |
-            Out-File "$dir.zip.sha256" -Encoding ascii
+          $h = (Get-FileHash "$dir.zip" -Algorithm SHA256).Hash.ToLower()
+          # LF, no BOM, "<hash>  <name>" — matches the unix `shasum` sidecar so
+          # `sha256sum -c` works cross-platform (Out-File would emit CRLF).
+          [IO.File]::WriteAllText((Join-Path $PWD "$dir.zip.sha256"), "$h  $dir.zip`n")
 
       - name: Attach to GitHub Release
         uses: softprops/action-gh-release@v2