Notebooks: ViewDefinition + SQLQuery cell types

[Panthevm]

Summary

• Two new cell types in the notebook editor and viewer: ViewDefinition and SQLQuery.
• Each cell uses a scoped ResourcePicker (now accepts kinds + placeholder) to choose a resource, shows the picked resource as a link with description, and provides a Run action that returns a tabular result.
• For SQLQuery the input parameters of Library.parameter[use=in] are rendered as labelled text inputs; their values are persisted inside cell.value as { url, params } JSON (with a backward-compatible fallback to a plain URL string).

Details

• ViewDefinitionCellView: POST /fhir/ViewDefinition/<id>/$run with a Parameters body; response is Binary with base64 JSON which is decoded into rows and rendered via HSComp.Table.
• SqlQueryCellView: POST /fhir/Library/<id>/$sqlquery-run with Parameters; parses parameter[name=row] into columns + rows.
• ResourcePicker: optional kinds: CandidateKind[] controls which FHIR endpoints are fetched, placeholder overrides the empty-state label.
• Editor: + dropdown grows two new entries; CellWrapper routes the new types to dedicated views.
• Default description on a freshly created notebook is now "Description".

Backend Notebook schema (zen + FHIR StructureDefinition) needs to accept the new enum values `view-definition` and `sql-query` (see the matching sansara/box change).

Test plan

• Open /notebooks/new, hit + → ViewDefinition, pick a view, press Run — table renders.
• Hit + → SQLQuery, pick a query that has parameters, fill them, press Run — table renders, parameters persist after Save/reload.
• Open the same notebook in view-mode — parameters remain editable and Run still works.
• The existing SQL builder still uses ResourcePicker as before.