fix: corriger InvalidUpgrade sur requêtes HTTP non-WebSocket

- process_request retourne None UNIQUEMENT pour /ws
- Tous les autres chemins (/favicon.ico, etc.) reçoivent 404
- Évite que websockets tente un handshake sur des requêtes HTTP normales

bot_direct.py

@@ -113,7 +113,10 @@ async def process_request(connection, request):
     if request.path == "/" or request.path == "/test.html":
         headers = Headers([("Content-Type", "text/html; charset=utf-8")])
         return Response(200, "OK", headers, HTML_PAGE.encode())
-    return None  # Let WebSocket handler take over
+    if request.path == "/ws":
+        return None  # Let WebSocket handler take over
+    # Return 404 for everything else (favicon, etc.)
+    return Response(404, "Not Found", Headers([]), b"")
 
 # ─── WebSocket Handler ───────────────────────────────────────
 async def ws_handler(websocket):