Adding remote schema fails when no tables exist

Just started a fresh project and tried to immediately add a remote schema. Didn't work. Adding a table fixed it

Reproduce the report in a fresh project by trying to add a remote schema before creating any tables, then repeat after adding a table to confirm the difference. Trace the remote-schema setup entry point and add a regression test showing that setup succeeds without tables; done means the original workflow works without the workaround.

Written by the indexing model from the issue text.