Bump actions/upload-artifact from 5 to 6

Bumps [actions/upload-artifact](https://github.com/actions/upload-artifact) from 5 to 6.
- [Release notes](https://github.com/actions/upload-artifact/releases)
- [Commits](https://github.com/actions/upload-artifact/compare/v5...v6)

---
updated-dependencies:
- dependency-name: actions/upload-artifact
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/build-to-release.yml

@@ -61,7 +61,7 @@ jobs:
         Write-Host "CLI executable ready: loaderspot-cli-win-$env:ARCH.exe"
 
     - name: Upload Windows artifacts
-      uses: actions/upload-artifact@v5
+      uses: actions/upload-artifact@v6
       with:
         name: windows-artifacts-${{ matrix.arch }}
         path: artifacts/*
@@ -110,7 +110,7 @@ jobs:
           echo "CLI executable ready: loaderspot-cli-linux-x64"
 
       - name: Upload Linux artifacts
-        uses: actions/upload-artifact@v5
+        uses: actions/upload-artifact@v6
         with:
           name: linux-artifacts-x64
           path: artifacts/*