[Feature Request] Support for "Send Typing" trigger from Bot Builder

[mysubcult]

Hello, Remi!

I have configured a bot in the Bot Builder that uses the "Send Typing" trigger (to simulate that the operator/bot is thinking before sending a message).

Current behavior:
When the bot reaches the "Send Typing" step, the delay works (the bot waits), but the Telegram user does not see the "Typing..." status in the chat header. It works perfectly in the Web Widget, but not in Telegram.

Expected behavior:
When the Bot Builder executes the "Send Typing" command, the extension should send a sendChatAction request to the Telegram API so the user sees "typing..." status.

Technical details:
I checked bootstrap.php and didn't find a listener that handles the typing event from the Generic Bot.
It seems we need to implement Longman\TelegramBot\Request::sendChatAction when the bot triggers the typing command.

Could you please add support for this?

Environment:

• LHC Version: Latest
• Telegram Extension: Latest

Thank you for your great work!