Add requires_zed_cla column to channels table

Don't allow granting guests write access in a call where the channel
or one of its ancestors requires the zed CLA, until that guest has
signed the Zed CLA.

Co-authored-by: Marshall <marshall@zed.dev>
25708088b7Max Brunsfeld committed on 1/23/2024, 12:41:24 AMparent676d2cb
14 files changedLine totals unavailable