Prebuilt workspaces should work in any organization

[SasSwart]

The prebuilds system user needs to be able to manage workspaces in multiple organisations. As such, it must be a member of any organisation that needs prebuilds. When the prebuild reconciliation loop runs, it should check for any organisations that need prebuilds for which the system user is not yet a member. The reconciliation loop must then add the user as a member to those organisations.

          I think you'll need to insert a prebuilds user for each organization. This will probably need to be a follow-up.

Originally posted by @johnstcn in coder/coder#16916 (comment)