Put Pages moves from namespace renames and transfers in Sidekiq
When we rename or transfer a namespace, any projects in that namespace with Pages
enabled have to have their directories moved on the filesystem to match.
We want all operations that touch Pages disk paths to happen in Sidekiq,
not Puma; this puts that in Sidekiq behind the
async_pages_move_namespace_rename
and async_pages_move_namespace_transfer
feature flags.
Like !40087 (merged), but for namespace moves.
For #235808 (closed).
Edited by Sean McGivern