ci(infra): 完整 CI/CD 流水线配置

- ci-ts.yml: lint/typecheck/test/build + arch-scan + docker-build（classes + teacher-portal）

- ci-go.yml: vet/build/test + docker-build（api-gateway）

- ci-proto.yml: buf lint + buf breaking（本地 .git 比较）

- docker.yml: main/tag 触发，构建推送 3 服务镜像到 Gitea Registry

- deploy.yml: workflow_dispatch + workflow_run 触发，Runner 直接 docker compose 部署，含健康检查与回滚

- 所有 workflow runs-on: ubuntu-latest 匹配 actrunner 标签

.github/workflows/docker.yml

@@ -0,0 +1,84 @@
+name: Docker Build & Push
+
+# 触发条件：main 分支推送 或 打 v* tag
+# 镜像推送到 Gitea Container Registry: git.eazygame.cn/xiner/edu/<service>:<tag>
+on:
+  push:
+    branches: [main]
+    paths:
+      - 'services/api-gateway/**'
+      - 'services/classes/**'
+      - 'apps/teacher-portal/**'
+      - 'packages/shared-proto/**'
+      - '.github/workflows/docker.yml'
+    tags:
+      - 'v*'
+
+permissions:
+  packages: write
+  contents: read
+
+env:
+  REGISTRY: git.eazygame.cn
+  OWNER: xiner
+  REPO_LOWER: edu
+
+jobs:
+  build-push:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        service:
+          - { name: api-gateway, dockerfile: services/api-gateway/Dockerfile, context: ./services/api-gateway }
+          - { name: classes, dockerfile: services/classes/Dockerfile, context: . }
+          - { name: teacher-portal, dockerfile: apps/teacher-portal/Dockerfile, context: . }
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: docker/setup-buildx-action@v3
+
+      # 登录 Gitea Container Registry
+      # GITHUB_TOKEN 由 Gitea Actions 自动注入，对应仓库写权限
+      - name: Login to Gitea Container Registry
+        uses: docker/login-action@v3
+        with:
+          registry: ${{ env.REGISTRY }}
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      # 生成镜像 tag
+      # main 分支：latest + git-sha
+      # v* tag：v<version> + latest
+      - name: Extract metadata
+        id: meta
+        uses: docker/metadata-action@v5
+        with:
+          images: ${{ env.REGISTRY }}/${{ env.OWNER }}/${{ env.REPO_LOWER }}/${{ matrix.service.name }}
+          tags: |
+            type=raw,value=latest,enable={{is_default_branch}}
+            type=sha,prefix={{branch}}-,enable={{is_default_branch}}
+            type=semver,pattern=v{{version}}
+            type=semver,pattern=v{{major}}.{{minor}}
+            type=ref,event=branch
+
+      - name: Build and push ${{ matrix.service.name }}
+        uses: docker/build-push-action@v5
+        with:
+          context: ${{ matrix.service.context }}
+          file: ${{ matrix.service.dockerfile }}
+          push: true
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
+          provenance: false
+
+      - name: Summary
+        run: |
+          echo "### Docker 镜像已推送" >> $GITHUB_STEP_SUMMARY
+          echo "" >> $GITHUB_STEP_SUMMARY
+          echo "服务：\`${{ matrix.service.name }}\`" >> $GITHUB_STEP_SUMMARY
+          echo "镜像标签：" >> $GITHUB_STEP_SUMMARY
+          echo '```' >> $GITHUB_STEP_SUMMARY
+          echo "${{ steps.meta.outputs.tags }}" >> $GITHUB_STEP_SUMMARY
+          echo '```' >> $GITHUB_STEP_SUMMARY