Migrate Domain scope ownership data to the Virtual Scope model

Migrate existing Domain scope ownership rows in association_scopes_entities into the Virtual Scope chain: backfill virtual_scopes rows for existing Domain owners, a self scope_binding per owner VS, scope_bindings for existing scope->Domain links, and entity_memberships for existing Domain->child ownership. Verify no ownership/permission regressions after migration.

[Aligned to BEP-1062 (#12842): correct table names are virtual_scopes / scope_bindings / entity_memberships (previously scope_virtual / virtual_entity, which do not exist in code). Resolution is non-recursive; ownership resolves via the self scope_binding.]

JIRA Issue: BA-6662

Start by locating the migration or data-access code for association_scopes_entities and the virtual_scopes, scope_bindings, and entity_memberships tables. Verify the backfilled rows, self scope_bindings, existing scope-to-Domain links, and Domain-to-child memberships, then check for ownership and permission regressions.

Written by the indexing model from the issue text.