v0.13.0

Optimising compiler — roadmap §4.4 (stored arrays → @derivedFrom).

Added

• W050 — stored array of entity references. The checker now flags an entity
  field typed [Child] (a stored array of another entity, not a derived from
  relation) and steers to @derivedFrom. graph-node keeps such arrays inline and
  rewrites the whole array into a new versioned row on every append, so a growing
  one-to-many is O(n²) on disk; a @derivedFrom reverse lookup is computed on
  read and never stored. Scalar and enum arrays ([String], [BigInt],
  [TokenStandard]) are genuinely stored values and are never flagged, and the
  recommended derived from form stays clean. The diagnostic suggests a concrete
  back-ref field name. Registered in redstart explain W050. Brings the
  diagnostic catalogue to 32 codes (26 errors, 6 warnings).

  Like W040, this is a warning rather than an auto-rewrite: the migration needs a
  back-ref field the author chooses (and it changes the stored data model), so it
  can't be applied mechanically the way immutability inference can.