[2026-05-15] Discord Stop 훅 추가 및 notifier User-Agent 수정

- .claude/discord_notify.py: 세션 종료 시 git log/status를 Discord로 전송
- .claude/settings.json: Stop 훅 등록
- notifier.py: Cloudflare 차단 방지를 위해 User-Agent 헤더 추가
- .gitignore: settings.local.json 제외

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

app/monitor/notifier.py

@@ -18,7 +18,8 @@ async def send(message: str) -> None:
         logger.warning(f"[Discord 미설정] {message}")
         return
     try:
-        async with aiohttp.ClientSession() as session:
+        headers = {"User-Agent": "DiscordBot (stockbot, 1.0)"}
+        async with aiohttp.ClientSession(headers=headers) as session:
             await session.post(
                 WEBHOOK_URL,
                 json={"content": message},