v0.40.0

Changed

• The vendored web component is @artooi/ag-ui-web-component@0.36.0, which
  settles a tool card to error or declined when TOOL_CALL_RESULT carries
  an outcome saying the call failed or was refused. Until now every result
  settled done, so a refused tool call rendered as a successful one with the
  reason folded inside it.

• The django-ag-ui floor is >=0.56, and it moves in the same release for
  a reason worth stating: 0.56 is what puts that outcome on the wire. Below it
  this package would ship a client watching for something its own server never
  sends, and every refused tool call would go on rendering as a success. The two
  halves are only right together.

  The previous floor's reason is subsumed, not dropped: 0.55 is where an
  endpoint with no model is refused at the mount rather than one request later.

Notes

• The adoption pass found nothing else owed, which is recorded because it is
  a result rather than a step that was skipped. All three of 0.36.0's entries
  are automatic -- the rendering is read by the component itself, and this
  package's own registered tools signal failure by throwing, which the component
  already maps to a failed outcome without being asked. Verified by grepping the
  vendored bundle for the new symbols and the host script for the calls, not by
  reading the changelog and assuming.