Reapply "ci: use GitHub Container Registry"

This reverts commit caf586f1ad.

.github/workflows/ci.yml

@@ -46,17 +46,18 @@ jobs:
     runs-on: ubuntu-latest
     permissions:
       contents: read
+      packages: write
     env:
-      IMAGE: git.maro.run/maro/anouma
+      IMAGE: ghcr.io/whitehai11/anouma
     steps:
       - name: Checkout
         uses: actions/checkout@v5
       - name: Log in to registry
         uses: docker/login-action@v3
         with:
-          registry: git.maro.run
-          username: ${{ secrets.REGISTRY_USERNAME }}
-          password: ${{ secrets.REGISTRY_PASSWORD }}
+          registry: ghcr.io
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
       - name: Build image
         run: docker build -t "$IMAGE:$GITHUB_SHA" .
       - name: Push image

.github/workflows/release.yml

@@ -6,19 +6,20 @@ on:
 
 permissions:
   contents: read
+  packages: write
 
 jobs:
   promote-and-deploy:
     runs-on: ubuntu-latest
     env:
-      IMAGE: git.maro.run/maro/anouma
+      IMAGE: ghcr.io/whitehai11/anouma
     steps:
       - name: Log in to registry
         uses: docker/login-action@v3
         with:
-          registry: git.maro.run
-          username: ${{ secrets.REGISTRY_USERNAME }}
-          password: ${{ secrets.REGISTRY_PASSWORD }}
+          registry: ghcr.io
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
       - name: Pull tested image
         run: docker pull "$IMAGE:$GITHUB_SHA"
       - name: Promote release image