So you are connecting to chat.
And logging all the messages sent in the channels you join.
That’s a chat bot when doing it progmatically.
Chatterino as Dist says is a client app, and that doesn’t go and mass join a load of channels using similar criteria to what you describe.
Make sure whatever you are doing is honoring the Developer agreement
https://www.twitch.tv/p/en-gb/legal/developer-agreement/
As just mass collecting peoples chat is a grey area.
Please make sure to opt out all channels I work with from your collection systems.
And provide a way for users and channels to opt out of your collection.
Please also do not collect chat messages sent by myself in channels I may or may not be in.