fix: ensure GHCR image tags use lowercase repository owner

.github/workflows/docker-image.yml

@@ -26,6 +26,10 @@ jobs:
           username: ${{ github.actor }}
           password: ${{ secrets.GITHUB_TOKEN }}
 
+      - name: Set lowercase repository owner
+        id: lowercase
+        run: echo "owner=$(echo '${{ github.repository_owner }}' | tr '[:upper:]' '[:lower:]')" >> "$GITHUB_OUTPUT"
+
       - name: Build and push
         uses: docker/build-push-action@v5
         with:
@@ -34,8 +38,8 @@ jobs:
           push: true
           platforms: linux/amd64,linux/arm64
           tags: |
-            ghcr.io/${{ github.repository_owner }}/moontv:latest
-            ghcr.io/${{ github.repository_owner }}/moontv:${{ github.sha }} 
+            ghcr.io/${{ steps.lowercase.outputs.owner }}/moontv:latest
+            ghcr.io/${{ steps.lowercase.outputs.owner }}/moontv:${{ github.sha }}
           cache-from: type=gha
           cache-to: type=gha,mode=max
 
@@ -45,4 +49,4 @@ jobs:
           token: ${{ secrets.GITHUB_TOKEN }}
           repository: ${{ github.repository }}
           retain_days: 0
-          keep_minimum_runs: 2
+          keep_minimum_runs: 2