feat: 接口字段补 @Schema 中文说明 + 精简冗余字段 + 接入 Prometheus 监控

- 全部 VO 字段补 @Schema(description) 中文说明，在线文档字段可读
- AppEpisodeVO 精简 duration/isFree 冗余字段（保留 durationSec/locked）
- framework 引入 actuator + micrometer-registry-prometheus
- SecurityConfig 放行 /actuator/prometheus，双服务配置 management 暴露指标
- 新增 deploy/docker-compose.yml + prometheus.yml 监控部署配置

deploy/docker-compose.yml

@@ -0,0 +1,32 @@
+# Author: fruit.com.cn
+# 监控组件编排：Prometheus + Grafana（Loki 日志后续接入）
+services:
+  prometheus:
+    image: prom/prometheus:latest
+    container_name: fruitshorts-prometheus
+    ports:
+      - "9090:9090"
+    volumes:
+      - ./prometheus.yml:/etc/prometheus/prometheus.yml
+      - prometheus-data:/prometheus
+    command:
+      - "--config.file=/etc/prometheus/prometheus.yml"
+    extra_hosts:
+      - "host.docker.internal:host-gateway"
+    restart: unless-stopped
+
+  grafana:
+    image: grafana/grafana:latest
+    container_name: fruitshorts-grafana
+    ports:
+      - "3000:3000"
+    volumes:
+      - grafana-data:/var/lib/grafana
+    environment:
+      - GF_SECURITY_ADMIN_USER=admin
+      - GF_SECURITY_ADMIN_PASSWORD=admin
+    restart: unless-stopped
+
+volumes:
+  prometheus-data:
+  grafana-data: