test: 添加E2E测试基础设施(docker-compose + seed + test)

docker-compose.e2e.yml启动Gitea+assistant；seed.sh自动创建用户/仓库/Webhook/PR；test.sh轮询验证AI评论出现

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

docker-compose.e2e.yml

@@ -0,0 +1,71 @@
+version: '3.8'
+
+# E2E 测试环境：Gitea + gitea-assistant
+# 用法:
+#   docker compose -f docker-compose.e2e.yml up -d
+#   # 等待服务启动后运行 seed 脚本:
+#   ./e2e/seed.sh
+#   # 运行 E2E 测试:
+#   ./e2e/test.sh
+#   # 清理:
+#   docker compose -f docker-compose.e2e.yml down -v
+
+services:
+  gitea:
+    image: gitea/gitea:1.22
+    container_name: e2e-gitea
+    environment:
+      - GITEA__database__DB_TYPE=sqlite3
+      - GITEA__server__ROOT_URL=http://gitea:3000
+      - GITEA__server__HTTP_PORT=3000
+      - GITEA__security__INSTALL_LOCK=true
+      - GITEA__service__DISABLE_REGISTRATION=false
+      - GITEA__service__REQUIRE_SIGNIN_VIEW=false
+      - GITEA__webhook__ALLOWED_HOST_LIST=*
+      - GITEA__webhook__SKIP_TLS_VERIFY=true
+    ports:
+      - "3333:3000"
+    volumes:
+      - gitea-data:/data
+    healthcheck:
+      test: ["CMD", "curl", "-f", "http://localhost:3000/api/v1/version"]
+      interval: 5s
+      timeout: 3s
+      retries: 20
+      start_period: 10s
+
+  assistant:
+    build:
+      context: .
+      dockerfile: Dockerfile
+    container_name: e2e-assistant
+    depends_on:
+      gitea:
+        condition: service_healthy
+    environment:
+      - NODE_ENV=production
+      - GITEA_API_URL=http://gitea:3000/api/v1
+      - GITEA_ACCESS_TOKEN=${E2E_GITEA_TOKEN:-placeholder}
+      - OPENAI_BASE_URL=${OPENAI_BASE_URL:-https://api.openai.com/v1}
+      - OPENAI_API_KEY=${OPENAI_API_KEY:-test_key}
+      - OPENAI_MODEL=${OPENAI_MODEL:-gpt-4o-mini}
+      - FEISHU_WEBHOOK_URL=http://localhost:9999/noop
+      - PORT=3000
+      - WEBHOOK_SECRET=e2e-test-secret
+      - REVIEW_ENGINE=agent
+      - REVIEW_WORKDIR=/tmp/e2e-review
+      - REVIEW_AUTO_PUBLISH_MIN_CONFIDENCE=0.5
+      - REVIEW_ENABLE_HUMAN_GATE=false
+      - REVIEW_ALLOWED_COMMANDS=git,rg,cat,sed,wc
+      - REVIEW_COMMAND_TIMEOUT_MS=30000
+    ports:
+      - "3334:3000"
+    healthcheck:
+      test: ["CMD", "curl", "-f", "http://localhost:3000/"]
+      interval: 5s
+      timeout: 3s
+      retries: 10
+      start_period: 5s
+
+volumes:
+  gitea-data: