feat(infra): p6 hardening - observability and deploy compose

- 5 NestJS services add /metrics endpoint via app.getHttpAdapter()
- prometheus.yml scales to 8 services with rule_files and alertmanager
- monitoring compose replaces blackbox with Loki+Promtail
- Grafana datasource adds Loki
- docker-compose.deploy.yml scales to 11 services
- deploy.env.example completes Neo4j/ES/ClickHouse/LLM vars
- teacher-bff adds health.controller
- CI removes continue-on-error on lint step
- teacher-portal lint script changed to eslint src

infra/deploy.env.example

@@ -27,12 +27,29 @@ JWT_AUDIENCE=next-edu-cloud
 API_GATEWAY_PORT=8080
 TEACHER_PORTAL_PORT=3000
 
-# ============ Kafka（P3 阶段启用，P1 留空）============
+# ============ Kafka（P3+ 启用，留空则 Outbox publisher 持续重试）============
 KAFKA_BROKERS=
 
-# ============ 可观测性（P6 阶段启用，P1 留空）============
-OTEL_EXPORTER_OTLP_ENDPOINT=
+# ============ 可观测性（P6 启用）============
+# OTLP collector 端点，留空则服务跳过 trace 上报
+OTEL_EXPORTER_OTLP_ENDPOINT=http://otel-collector:4318
 LOG_LEVEL=info
 
-# ============ 镜像 tag（由 CI 注入，手动部署时可改）============
-# IMAGE_TAG=latest  ← 默认 latest，CI 通过 export IMAGE_TAG 覆盖
+# ============ Neo4j（content 服务，留空则降级模式）============
+NEO4J_URL=
+NEO4J_PASSWORD=
+
+# ============ Elasticsearch（msg 服务，留空则降级模式）============
+ES_URL=
+
+# ============ ClickHouse（data-ana 服务，留空则降级模式）============
+CLICKHOUSE_HOST=
+CLICKHOUSE_PORT=8123
+CLICKHOUSE_DATABASE=edu_analytics
+CLICKHOUSE_USER=
+CLICKHOUSE_PASSWORD=
+
+# ============ LLM 配置（ai 服务，留空则降级模式）============
+OPENAI_API_KEY=
+OPENAI_BASE_URL=https://api.openai.com/v1
+ANTHROPIC_API_KEY=