fix: Fixes room alias resolution error handling

Ensures room ID is returned only if present in the response
Improves reliability by returning the alias if resolution fails

src/matrix_roomba/bot.py

@@ -138,7 +138,12 @@ class RoombaBot:
         Returns:
             str: The room ID of the resolved room alias.
         """
-        return await self.client.room_resolve_alias(room_alias)
+        response = await self.client.room_resolve_alias(room_alias)
+
+        if response and "room_id" in response:
+            return response["room_id"]
+
+        return room_alias
 
     async def block_room(self, room_id, block):
         """Block or unblock a room.