Usage flags need more attention

[museun]

rm Env:\STREAMCHAT_TWITCH_OAUTH_TOKEN
streamchatc --standalone

when not using the config file, the env variable STREAMCHAT_TWITCH_OAUTH_TOKEN must be set to your Twitch OAUTH token

Its an error to use --standalone without the env var set. This implies that the oauth token can be used in streamchatc.toml. I don't want the token to be there, so the error should reflect it.