add MyTonCtrl alert bot docs (#790)

* add MyTonCtrl alert bot docs

* update sidebars

docs/participate/run-nodes/alerting.md

@@ -0,0 +1,55 @@
+# MyTonCtrl Alert Bot
+
+## Overview
+
+MyTonCtrl Alert Bot is a tool that allows you to receive notifications about the status of your node via Telegram Bot. 
+It is a part of the MyTonCtrl toolset and is available for both validators and liteservers. 
+
+## Setup
+
+To set up the MyTonCtrl Alerting Bot, follow these steps:
+
+### Prepare bot
+
+1. Go to https://t.me/BotFather and create bot using command `/newbot`. After that, you will receive a `BotToken`.
+2. Go to your bot and press the `Start` button. This will allow you to receive messages from the bot.
+3. If you want to receive messages from the bot in a group (chat), add the bot to the group and give it the necessary rights (make group admin).
+4. Go to https://t.me/getmyid_bot and press the `Start` button. It will reply you with your `ChatId`, use that if you want to receive messages directly to your Telegram account.
+If you want to receive messages in a group, add the bot to the group, and it will reply with the `ChatId` of the group.
+
+### Enable the Alert Bot
+
+1. Enable `alert-bot` via command
+
+    ```bash
+    MyTonCtrl> enable_mode alert-bot
+    ```
+2. Run command
+
+    ```bash
+    MyTonCtrl> set BotToken <BotToken>
+    ```
+3. Run command
+
+    ```bash
+    MyTonCtrl> set ChatId <ChatId>
+    ```
+4. Restart `mytoncore` service using command 
+
+    ```bash
+   $ sudo systemctl restart mytoncore
+    ```
+
+## Supported Alerts
+
+The MyTonCtrl Alert Bot supports the following alerts:
+
+* Validator's wallet balance is low
+* Node's db usage is more than 80%
+* Node's db usage is more than 95%
+* Validator had low efficiency in the round
+* Node is out of sync
+* Node is not running (service is down)
+* Node is not answering to ADNL connection
+* Validator created zero blocks for past 6 hours
+* Validator has been slashed in the previous validation round

sidebars/develop.js

@@ -214,6 +214,7 @@ module.exports = [
         label: 'MyTonCtrl',
         items: [
           'participate/run-nodes/mytonctrl',
+          'participate/run-nodes/alerting',
           'participate/run-nodes/mytonctrl-status',
         ],
       },