Add Telegram bot and API client integration with SSE support

api_client.py

@@ -0,0 +1,61 @@
+"""율봇 API 클라이언트 — youlbot REST API를 httpx로 호출."""
+import json
+import os
+from typing import AsyncIterator
+
+import httpx
+from dotenv import load_dotenv
+
+load_dotenv()
+
+_API_URL = os.getenv("YOULBOT_API_URL", "http://localhost:8000").rstrip("/")
+_API_TOKEN = os.getenv("YOULBOT_API_TOKEN", "")
+
+
+def _headers() -> dict:
+    if _API_TOKEN:
+        return {"Authorization": f"Bearer {_API_TOKEN}"}
+    return {}
+
+
+async def chat(
+    message: str,
+    user_id: str = "default",
+    show_thinking: bool = False,
+) -> AsyncIterator[tuple[str, str | None]]:
+    """SSE 스트림을 읽어 (token, run_id) 튜플을 yield.
+
+    - 일반 토큰: (token_str, None)
+    - 스트림 종료: ("", run_id_or_None)  ← __done 이벤트
+    """
+    async with httpx.AsyncClient(timeout=180) as client:
+        async with client.stream(
+            "POST",
+            f"{_API_URL}/chat",
+            json={"message": message, "user_id": user_id, "show_thinking": show_thinking},
+            headers=_headers(),
+        ) as response:
+            response.raise_for_status()
+            async for line in response.aiter_lines():
+                if not line.startswith("data: "):
+                    continue
+                raw = line[6:]
+                try:
+                    payload = json.loads(raw)
+                except json.JSONDecodeError:
+                    yield raw, None
+                    continue
+                if isinstance(payload, dict) and payload.get("__done"):
+                    yield "", payload.get("run_id")
+                    return
+                yield payload, None
+
+
+async def reset(user_id: str = "default") -> None:
+    async with httpx.AsyncClient(timeout=30) as client:
+        r = await client.post(
+            f"{_API_URL}/reset",
+            params={"user_id": user_id},
+            headers=_headers(),
+        )
+        r.raise_for_status()