Native tenant source-layout examples

These canonical layouts use the current tenant runtime and its native component registry.
They are source examples, not tenant installation or publication receipts.
Account Administration requires module.account-admin, which is not registered in this
kit's portable page schema. Its two examples require the matching native runtime registry;
do not bypass schema validation or invent component IDs to import them.
Other examples still require matching component versions, permissions and typed APIs.
See ../../docs/NATIVE-LEGO-BUILDER-GUIDE.txt for placement and draft-safety rules.
