client.get_dialogs doesn't work with bot identity.

https://github.com/chigwell/telegram-mcp/blame/71cdefa55cccf6bd24f8472fae1df81d83f4df04/main.py#L4725

I use a bot identity (not a full user)

failing here due to `BotMethodInvalidError: The API access for bot users is restricted. The method you tried to invoke cannot be executed as a bot (caused by GetDialogsRequest)`

Thanks