ci: build Docker images, publish to GHCR

.github/workflows/MinedMap.yml

@@ -1,5 +1,14 @@
 name: 'MinedMap'
-on: ['push', 'pull_request', 'workflow_dispatch']
+on:
+  push:
+    branches:
+      - 'main'
+    tags:
+      - 'v*'
+  pull_request:
+    branches:
+      - 'main'
+  workflow_dispatch: {}
 
 env:
   RUSTFLAGS: -Dwarnings
@@ -139,3 +148,78 @@ jobs:
         with:
           name: 'MinedMap-${{ steps.tag.outputs.tag }}-${{ matrix.target }}'
           path: 'target/pkg'
+
+  build-container:
+    runs-on: ubuntu-latest
+    needs:
+      - test
+    steps:
+      - name: Docker meta
+        id: meta
+        uses: docker/metadata-action@v5
+        with:
+          images: |
+            ghcr.io/neocturne/minedmap/minedmap
+          tags: |
+            type=raw,value=latest,enable={{is_default_branch}}
+            type=ref,event=branch
+            type=ref,event=branch,suffix=-{{sha}}
+            type=ref,event=pr
+            type=semver,pattern={{version}}
+            type=semver,pattern={{major}}.{{minor}}
+            type=semver,pattern={{major}}
+
+      - name: Login to GHCR
+        if: github.event_name != 'pull_request'
+        uses: docker/login-action@v3
+        with:
+          registry: ghcr.io
+          username: ${{ github.repository_owner }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - uses: docker/setup-buildx-action@v3
+
+      - name: Build
+        uses: docker/build-push-action@v6
+        with:
+          push: ${{ github.event_name != 'pull_request' }}
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}
+
+  viewer-container:
+    runs-on: ubuntu-latest
+    needs:
+      - test
+    steps:
+      - name: Docker meta
+        id: meta
+        uses: docker/metadata-action@v5
+        with:
+          images: |
+            ghcr.io/neocturne/minedmap/viewer
+          tags: |
+            type=raw,value=latest,enable={{is_default_branch}}
+            type=ref,event=branch
+            type=ref,event=branch,suffix=-{{sha}}
+            type=ref,event=pr
+            type=semver,pattern={{version}}
+            type=semver,pattern={{major}}.{{minor}}
+            type=semver,pattern={{major}}
+
+      - name: Login to GHCR
+        if: github.event_name != 'pull_request'
+        uses: docker/login-action@v3
+        with:
+          registry: ghcr.io
+          username: ${{ github.repository_owner }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - uses: docker/setup-buildx-action@v3
+
+      - name: Build
+        uses: docker/build-push-action@v6
+        with:
+          context: "{{defaultContext}}:viewer"
+          push: ${{ github.event_name != 'pull_request' }}
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}