kdiff 0.3.0

Added

• A @DiffKey value must identify at most one element in a list. Comparing or applying a keyed list
  whose elements share a key throws IllegalArgumentException, naming the property, the key property
  and the duplicated value.

  Such a list has no diff to report: a path identifies a keyed element by its key value, so
  addresses[id=A1] cannot say which of two elements it means, and distinguishing them would need a
  change variant the closed vocabulary does not have. It cannot be caught at compile time either —
  uniqueness is a property of the data, not of the declaration — so it is a runtime precondition, and
  both directions enforce it identically.

  If a key is not unique it is not an identity: drop @DiffKey from the element type, or describe the
  property with list rather than keyedList, and the list is compared by position instead, giving up
  move reporting.

• patchKeyedList takes name and keyProperty, so it can name the offending property in that
  message. Both default to null; a hand-written Patcher that omits them gets a message without them.
  Generated code passes both.

Changed

• The guides are corrected and extended: diagrams for the change and path model, under frame
  dispatch, depth counting, the module graph and the tutorial's command-to-events flow; a
  "Where to go next" footer on every page; sections in docs/architecture.md on what a comparison
  costs and what kdiff does not do; and DiffNode/tree() given a worked example.

• Documented coordinates are pinned to the published version by a test, so an install snippet cannot
  survive a release that leaves it behind.