v0.13.0

Minor release adding JSON Schema descriptions, model collection and state accessors, with breaking changes to custom validators and the default predicate namespace.

Added

• Let resource declare no members of its own: it now accepts extended shapes alone, shape-level constraints alone,
  extended shapes followed by constraints, or no arguments at all, carrying only the members it inherits
• Add getStateId and getStateEntries state accessors to @metreeca/blue/resource, returning the identifier of a
  validated state and its values as Entry records typed by the value shape each one matches
• Add schema to @metreeca/blue, describing the payloads a resource shape admits as a JSON Schema (draft 2020-12),
  with a strict variant keeping to the subset accepted by strict structured output generators
• Add model to @metreeca/blue, collecting entry shapes together with every shape they extend, link to or embed,
  each once and in a stable order, so model-wide encodings can cover the whole connected model

Fixed

• Reject reverse mappings on members whose range admits literals when the shape is built: a reverse mapping makes
  each value a subject, so it is admitted only over references, embedded resources, or unions of them

Changed

• Run the custom validators a resource shape states only where a whole resource is validated: validateResult and
  validate with a retrieval template no longer apply them, as a retrieval may leave out any member a check reads
• Resolve member predicates unqualified by a stated or inherited space against the base namespace (base:/#) of
  @metreeca/core/resource, which replaces the former app namespace and its app:/# origin in core 0.13.0
• Upgrade @metreeca/core to ^0.13.0
• Upgrade @metreeca/qest to ^0.13.0

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Full Changelog: v0.12.1...v0.13.0