feat(P3): 5개 서비스 비즈니스 이벤트 logger.info 보강

lotto/app/main.py

@@ -704,6 +704,7 @@ def api_recommend(
 
     metrics = calc_metrics(chosen)
     overlap = calc_recent_overlap(chosen, draws, last_k=avoid_recent_k)
+    logger.info(f"추천 생성 완료: numbers={chosen}, tries={tries}, saved={saved['saved']}")
 
     return {
         "id": saved["id"],

lotto/app/routers/briefing.py

@@ -1,9 +1,12 @@
 """브리핑 저장/조회 + 큐레이터 사용량 엔드포인트."""
+import logging
 from typing import Any, Dict, List
 from fastapi import APIRouter, HTTPException
 from pydantic import BaseModel, Field
 from .. import db
 
+logger = logging.getLogger(__name__)
+
 router = APIRouter(prefix="/api/lotto")
 
 
@@ -38,6 +41,7 @@ class BriefingRequest(BaseModel):
 @router.post("/briefing", status_code=201)
 def save_briefing(body: BriefingRequest):
     bid = db.save_briefing(body.model_dump())
+    logger.info(f"브리핑 저장 완료: id={bid}, draw_no={body.draw_no}, model={body.model!r}, input_tokens={body.tokens_input}, output_tokens={body.tokens_output}")
     return {"ok": True, "id": bid}