Fix GitHub Actions artifact upload deprecation

- Update upload-artifact from v3 to v4 in release.yml
- Update download-artifact from v3 to v4 in release.yml
- Update upload-artifact to v4 in publish.yml
- Use unique artifact names with target suffix to avoid conflicts
- Add merge-multiple flag for downloading artifacts

Fixes the "deprecated version" errors that were causing
workflow failures.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <[email protected]>

Author: tdi

.github/workflows/publish.yml

@@ -172,9 +172,9 @@ jobs:
     
     - name: Upload artifacts (manual trigger)
       if: github.event_name == 'workflow_dispatch'
-      uses: actions/upload-artifact@v3
+      uses: actions/upload-artifact@v4
       with:
-        name: binaries-${{ matrix.asset_name }}
+        name: binaries-${{ matrix.target }}
         path: |
           ${{ matrix.asset_name }}.tar.gz
           ${{ matrix.asset_name }}.tar.gz.sha256

.github/workflows/release.yml

@@ -77,9 +77,9 @@ jobs:
         sha256sum ${{ matrix.asset_name }}.tar.gz > ${{ matrix.asset_name }}.tar.gz.sha256
     
     - name: Upload artifacts
-      uses: actions/upload-artifact@v3
+      uses: actions/upload-artifact@v4
       with:
-        name: binaries
+        name: binaries-${{ matrix.target }}
         path: |
           *.tar.gz
           *.tar.gz.sha256
@@ -92,10 +92,11 @@ jobs:
     - uses: actions/checkout@v4
 
     - name: Download artifacts
-      uses: actions/download-artifact@v3
+      uses: actions/download-artifact@v4
       with:
-        name: binaries
         path: ./artifacts
+        pattern: binaries-*
+        merge-multiple: true
 
     - name: Extract version
       id: get_version