Refactor: Mem0-Sidecar nutzt lifespan statt deprecated on_event

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

mem0_service/app.py

@@ -20,6 +20,7 @@ Bind: 127.0.0.1 (nur lokal; MC2 proxyt nach außen).
 
 import logging
 import os
+from contextlib import asynccontextmanager
 
 from fastapi import FastAPI, HTTPException
 from pydantic import BaseModel
@@ -94,7 +95,6 @@ def build_memory() -> Memory:
     return m
 
 
-app = FastAPI(title="MC2 Mem0 Sidecar")
 _mem: Memory | None = None
 
 
@@ -105,14 +105,18 @@ def mem() -> Memory:
     return _mem
 
 
-@app.on_event("startup")
-def _startup() -> None:
+@asynccontextmanager
+async def lifespan(_app: FastAPI):
     logging.basicConfig(level=logging.INFO)
     try:
-        mem()
+        mem()  # Memory beim Start aufbauen (Chroma öffnen, Modelle anpingen)
         log.info("Mem0 bereit (chroma=%s, embed=%s, llm=%s)", CHROMA_PATH, EMBED_MODEL, LLM_MODEL)
     except Exception:
         log.exception("Mem0-Init fehlgeschlagen (Dienst läuft, /health meldet down)")
+    yield
+
+
+app = FastAPI(title="MC2 Mem0 Sidecar", lifespan=lifespan)
 
 
 # --- Mapping Mem0 <-> MC2-API-Form -----------------------------------------------