Added folder function

[fbbDirge]

Clear and concise description of the problem

make channel categorization easier to manage

Suggested solution

I think we can add custom folders under each channel, and support drag-and-drop into the feed, so I think it will be better

Alternative

No response

Additional context

No response

Validations

• [x] Check that there isn't already an issue that request the same feature to avoid creating a duplicate.

[linear[bot]]

FOL-808 Added folder function