- The changelog's 4.6.0 section loses "(unreleased)": Arcade as ARC (i5he),
  received payments submitted in Extended Format (3qt8), in-flight answers
  followed by SubmissionWatcherActor (2t5z).
- pubspec 4.6.0; README installs libspiffy ^4.6.0.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>