improve UX of bot's "sendMoney" command

[Sladuca]

Currently sendMoney is very crude and doesn't yet have support for NE5 Tokens, even though we eventually want it to. We need to re-structure the command so that it works.

In the bot subrepo, in commands/Send.ts:

• rename "sendMoney" command to "send"
• add an error message to "send"command that says something along the lines of "unsupported asset type" whenever the asset argument given is not supported. For now this error should happen for every asset that isn't $NEAR.

In the bot subrepo, in config/config.ts, change the current activity of the bot. name can be literally any string, and type can be one of the strings listed here