feat: For bots, wait with emitting IncomingMsg until the Post-Msg arrived

src/context.rs

@@ -1146,6 +1146,12 @@ ORDER BY m.timestamp DESC,m.id DESC",
     ///
     /// Blocked contacts and chats are excluded,
     /// but self-sent messages and contact requests are included in the results.
+    ///
+    /// Note that this returns the pre-message's id as soon as it arrives.
+    /// The bot needs to wait for the post-message by itself if it wants to use this API
+    /// to get fully downloaded messages.
+    /// If the bot doesn't want this, then it should instead use the [`EventType::IncomingMsg`]
+    /// event for getting notified about new messages.
     pub async fn get_next_msgs(&self) -> Result<Vec<MsgId>> {
         let last_msg_id = match self.get_config(Config::LastMsgId).await? {
             Some(s) => MsgId::new(s.parse()?),