ci: Use GHCR_TOKEN secret for package authentication

Switch from GITHUB_TOKEN to personal access token stored in secrets
to resolve package write permission issues.

Author: CodeKeanu

.github/workflows/docker-publish.yml

@@ -33,8 +33,8 @@ jobs:
         uses: docker/login-action@v3
         with:
           registry: ${{ env.REGISTRY }}
-          username: ${{ github.actor }}
-          password: ${{ secrets.GITHUB_TOKEN }}
+          username: ${{ github.repository_owner }}
+          password: ${{ secrets.GHCR_TOKEN }}
 
       - name: Extract metadata (tags, labels) for Docker
         id: meta