v0.63.0 — the server carries meta-model v0.90.0 and serves the landscape pack

The server carries meta-model v0.90.0 (#159). An instance that takes the landscape pack is served with its system, system-kind, data-object and service pages: list_types and describe_schema show the four types against the pack's schemas, get_entity on a system returns its ## Connects to and ## Holds rows with the service, the concept carried and the data object resolved as the row's attributes (R16) and the interface, the protocol and the access mode as values, list_references shows a feature's inverse edge from the system that realizes it, and diagram draws the landscape edges into a neighborhood. A product's kind is a required reference to a product kind, which describe_schema("product") says. The test fixtures derive each pack's folders from the release's PACKS, so a fourth pack needs no hand edit.

What breaks. Nothing for a host: the server reads whatever packs the instance it serves took.

How to take it. A host moves its pin to 0.63.0 and re-deploys; the content pin may move at the same time to an instance commit on core 0.65.0.

Verified: npm test, build:check, typecheck and the conventions check and format pass on the branch.