feat: add GHCR container images

Signed-off-by: Devin Buhl <devin@buhl.casa>

.github/workflows/docker.yml

@@ -60,7 +60,9 @@ jobs:
         id: meta
         uses: docker/metadata-action@v5
         with:
-          images: ${{matrix.image}}
+          images: |
+            docker.io/${{matrix.image}}
+            ghcr.io/${{matrix.image}}
           tags: |
             type=edge
             type=ref,event=branch
@@ -85,6 +87,14 @@ jobs:
           username: ${{ secrets.DOCKER_USERNAME }}
           password: ${{ secrets.DOCKER_PASSWORD }}
 
+      - name: Login to GitHub Container Registry
+        if: env.SHOULD_PUSH == 'true'
+        uses: docker/login-action@v3
+        with:
+          registry: ghcr.io
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
       - name: Build and push
         id: docker_build
         uses: docker/build-push-action@v5