feat(analytics): 埋点事件接收接口 + admin 查询接口 + 埋点表 (#81)

新手引导埋点的服务端:
- 表 analytics_event(五维硬性列 + props JSON 扩展字段;event/device_id/user_id/session_id/created_at 带索引)
- POST /api/v1/analytics/events:客户端批量上报(不鉴权、body 读可选 user_id、补 client_ip + server_at)
- admin GET /admin/api/event-logs:列表 + 按 事件/设备/用户/会话/时间 筛选(offset 分页,照 list_feedbacks)
- alembic migration 建表(autogenerate 顺带检出的 ad/cps 历史索引漂移已手动剔除)

app 主后端 :8770 与 admin :8771 共用同一 SQLite,admin 同库直接查、无需跨库。
配套客户端五维上报 + admin 日志页(另两仓库 PR)。

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

---------

Co-authored-by: zzhyyyyy <2685922758@qq.com>
Reviewed-on: #81
Co-authored-by: zhuzihao <zhuzihao@wonderable.ai>
Co-committed-by: zhuzihao <zhuzihao@wonderable.ai>

app/main.py

@@ -15,6 +15,7 @@ from fastapi.middleware.cors import CORSMiddleware
 from fastapi.staticfiles import StaticFiles
 
 from app.api.v1.ad import router as ad_router
+from app.api.v1.analytics import router as analytics_router
 from app.api.v1.auth import router as auth_router
 from app.api.v1.compare import router as compare_router
 from app.api.v1.compare_milestone import router as compare_milestone_router
@@ -105,6 +106,7 @@ def health() -> dict[str, str]:
 app.include_router(auth_router)
 app.include_router(user_router)
 app.include_router(feedback_router)
+app.include_router(analytics_router)
 app.include_router(invite_router)
 app.include_router(coupon_router)
 app.include_router(device_router)