UX improvements driven by live testing:
- setMyCommands populates Telegram's '/' picker with all commands and
descriptions, so the operator gets autocomplete instead of guessing
syntax.
- /start replies with an inline keyboard ([📒 Accounts] [📡 How to Pair]
[❓ Help]) — quick navigation without typing.
- /accounts emits one message per account with [📂 Groups] [🗑 Unpair]
inline buttons. Tapping triggers a callback (no typed labels needed).
- New callbacks module wires the buttons. Unpair shows a confirm/cancel
prompt before acting.
/pair still requires a typed label since the value is operator-defined
content rather than a selection from existing data.